AGR1C,  DEPT, 


FOOD  INDUSTRIES 

t 

An  Elementary  Text-book  on  the  Produc- 
tion and  Manufacture  of  Staple  Foods 


DESIGNED  FOR  USE  IN  HIGH 
SCHOOLS  AND  COLLEGES 


by 


HERMANN  T.  VULTE,  Ph.D.,F.CS. 

Assistant  Professor  Household  Arts,  Teachers  College,  Columbia  University 


an< 


SADIE  B.  VANDEkBlLT,  B.S. 

Instructor  Household  Arts,  Teachers  College,  Columbia  University 


EASTON,  PA.: 

THE  CHEMICAL  PUBLISHING  CO. 
1914 


:- 


COPYRIGHT,  1914,  BY  H.  T.  VUI/TE 


-     ..,.•; 
.  »   • 

.  • .•    • 


:'H..\:^} 


PREFACE. 

After  many  years'  experience  in  lecturing  on  the  processes  of 
food  manufacture,  the  authors  feel  encouraged  to  submit  the 
result  of  their  labors  as  a  guide  to  those  who  wish  to  study  this 
most  important  and  interesting  subject. 

Certainly  no  branch  of  general  manufacturing  has  undergone 
so  many  and  such  important  changes  in  the  past  twenty-five  years 
as  the  food  industries.  The  public  have  largely  benefitted  from 
these  changes  both  in  pocket  and  health. 

Unfortunately  there  still  lingers  in  the  minds  of  many,  the 
impression  that  food  stuffs  have  not  the  same  dietetic  value  they 
possessed  in  the  past,  and  that  manipulation  gives  them  an  appear- 
ance of  quality  they  do  not  possess.  It  is  the  universal  experi- 
ence of  the  authors  that  manufacturers  have  not  only  improved 
the  quality  of  their  products  in  every  possible  way,  but  having 
nothing  to  conceal  except  from  competitors,  are  most  anxious  to 
enlighten  the  interested  consumer  in  the  processes  involved. 

Some  mistakes  have  certainly  been  made  in  the  past,  but  with 
no  evil  intent  and  largely  through  ignorance.  As  time  passes 
these  errors  are  corrected  and  it  can  confidently  be  stated  that 
the  public  receives  to-day  better  and  cleaner  material  at  a  lower 
price  than  formerly.  The  economic  improvement  is  largely  due 
to  the  general  utilization  of  by-products,  many  of  which  do  not 
appear  in  any  list  of  foods. 

The  following  pages  do  not  claim  to  deal  with  any  industry 
from  the  purely  technical  standpoint,  but  aim  to  point  out  the 
most  essential  parts  of  each.  A  knowledge  of  chemistry  and 
physics  is  not  absolutely  essential,  but  is  very  helpful. 

As  a  pioneer  book  on  the  subject,  any  suggestions  furnished 
by  teachers  would  be  very  gratefully  received. 

The  authors  are  greatly  indebted  to  Dr.  H.  C.  Humphrey, 
Dr.  W.  D.  Home,  Dr.  W.  E.  J.  Kirk,  Mr.  George  S.  Ward  and 
Mr.  Earl  D.  Babst  for  valuable  suggestions  in  regard  to  the 
subject  matter  of  this  book  and  to  Mrs.  Ellen  B.  McGowan  of 
Teachers  College  for  reading  the  manuscript.  They  wish  also 
to  acknowledge  the  assistance  of  the  many  manufacturers  who 
have  thrown  their  plants  open  for  inspection  and  who  have 
allowed  the  use  of  photographs  and  cuts  of  machinery. 
September,  ,9x4.  ^ 


TABLE  OF  CONTENTS. 


PAGE 

Introduction  1-4 

Chapter  I — Food  Principles 5-15 

Functions.  Conservation  of  Energy.  Elements  in 
Foods.  Food  Principles.  Examples  of  Each  Group. 
Functions  of  Each  Group.  Importance  of  Water. 
Carbohydrates.  Classification.  Formation.  Occur- 
rence. Important  Properties.  Hydrolysis.  Fats. 
Composition.  Occurrence.  Properties.  Solubility. 
Change  of  State.  Crystallization.  Drying  and  Non- 
drying.  Emulsification.  Saponification.  Proteins. 
Composition.  Classification.  Occurrence.  Protein 
Hydrolysis.  Properties.  Solubility.  Curdling. 
Coagulation.  Clotting. 

Chapter  II — Water   16-35 

Classification  of  Natural  Waters.  Water  Supply. 
Historical.  Classification  of  Potable  Water.  Atmos- 
pheric. Surface  Water.  Subsoil  Water.  Pollution 
of  Wells.  Contamination  of  Public  Supplies.  Danger 
of  Impure  Water.  Diseases  from  Water.  Purifica- 
tion of  Water.  Public  Methods.  Bacterial  Action. 
Filtration.  Use  of  Chemical  Agents.  Household 
Methods.  Boiling.  Use  of  Domestic  Filters. 
Manufacturers'  Methods.  Self-purification.  Judg- 
ing a  Water  Supply.  Ice  Supply.  Mineral  Waters. 
Classification.  Natural  Mineral  Springs.  Occur- 
rence. Medicinal  Power.  Artificial  Mineral  Waters. 

Chapter  III— The    King    of     Cereals.       Old     Milling 

.     Processes   36-5 1 

Wheat.  Origin.  Geographical  Distribution.  Culti- 
vation. Structure  of  the  Wheat  Grain.  Value  of 
Wheat.  Varieties.  Old  Milling  Processes.  Hand- 
stones.  The  Pestle  and  Mortar.  The  Quern.  The 
Grist  Mill.  Disadvantages  of  Old  Processes. 

Chapter  IV — Modern  Milling  and  Mill  Products 52~6$ 

Dust  Collectors.  Fundamental  Objects  in  Milling. 
Cleaning  of  the  Wheat.  Tempering.  Separation  of 
the  Middlings.  Reduction  of  the  Middlings.  Advan- 


•  CONTENTS  V 

PAGE 

tages  of  the  New  Process.  Testing  of  Flour.  Wheat 
Blends.  Adulteration.  Bleaching  of  Flour.  Mill 
Products.  Hard  Wheat  Flour.  Soft  Wheat  Flour. 
Prepared  Flour.  Graham  Flour.  Entire  Wheat 
Flour.  Gluten  Flour.  Cereal  Department.  Seminola. 
Rye.  Composition.  Uses.  Adulteration. 

Chapter  V— Cereals   66-76 

Biological  Origin.  Kinds.  Geographical  Distribution. 
Use  in  Our  Country.  Indian  Corn  or  Maize.  Origin. 
Early  Cultivation.  Varieties.  Early  Methods  of 
Preparation.  Old  Milling  Methods.  Samp.  Hominy 
and  Cornmeal.  Modern  Milling.  Uses.  Adultera- 
tion. Rice.  Origin.  Geographical  Distribution. 
Composition.  Cultivation.  Milling.  Adulteration. 
Uses.  Oats.  Composition.  Oatmeal.  Milling. 
Adulteration.  Barley.  Origin.  Cultivation.  Com- 
position. Uses.  Mill  Products. 

Chapter  VI-f-Breakfast  Foods  and  Coffee  Substitutes.  .       77-83 
Breakfast  Foods.     Classification.     Uncooked.     Partly 
Cooked.     Cooked.     Malted   Preparations.     Adultera- 
tion.    Comparison  of  Old  and  New  Cereals.     Coffee 
Substitutes. 

Chapter  VII — Utilization  of  Flour.  Breadmaking.  .  .  .  84-106 
Primitive  Breadmaking.  Leavened  Bread.  Flour. 
Water.  Salt.  Yeast.  Leavening  Effect  of  Yeast. 
Yeast  Preparations.  Home  Brew.  Brewer's  Yeast 
Compressed  Yeast.  Dried  Yeast.  Object  in  Bread- 
making.  Steps  in  Breadmaking.  Fermentation. 
Straight  or  Off-Hand  Dough.  Ferment  and  Dough. 
Sponge  and  Dough.  Baking.  Cooling.  A  Modern 
Bread  Factory.  Souring  and  Its  Prevention.  Adul- 
teration. Losses  in  Fermentation.  Chemical  Process. 
Aerated  Bread.  Crackers.  Macaroni.  Manufactur- 
ing Processes.  Domestic  Macaroni.  Judging  Quality. 
As  a  Food. 

Chapter  VIII— Leavening  Agents   107-116 

Advantages  of  Yeast.  Chemical  Agents.  Advan- 
tages. Disadvantages.  Baking  Powders.  Tartrate 


VI  CONTENTS 

\ 

Powder.  Phosphate  and  Alum  Powders.  Compari- 
son of  Tartrate,  Phosphate  and  Alum  Phosphate 
Powders.  Relative  Efficiency.  Ammonia  Powders. 
Cream  of  Tartar.  Tartaric  Acid.  Acid  Phosphate 
of  Lime.  Bicarbonate  of  Soda.  LeBlanc  Method. 
Solvay  Process.  Niagara  Process. 

Chapter  IX — Starch  and  Allied  Industries 117-129 

Starch.  Composition  and  Formation.  Physical 
Characteristics.  Physical  and  Chemical  Properties. 
Uses.  Source  of  Supply.  Potato  Starch.  Extrac- 
tion. Processes  in  Manufacture.  Tapioca.  Corn 
Products  Industry.  Processes  in  Manufacture.  By- 
products and  Their  Uses.  Dextrins.  Uses.  Corn 
Syrup  or  Glucose.  Uses.  Processes  in  Manufacture. 

Chapter  X — The  Sugar  Industry 130-152 

Source.  History  of  the  Sugar  Cane.  History  of  the 
Sugan  Beet.  Comparison  of  Cane  and  Beet  Sugar. 
Properties  of  Sugar.  The  Cane  Sugar  Industry. 
Growth  of  the  Cane.  Production  of  Raw  Gene 
Sugar.  The  Beet  Sugar  Industry.  Beet  Culture. 
Production  of  Raw  Beet  Sugar.  Refining  of  Raw 
Sugar.  Granulated  Sugar.  Block  Sugar.  Powdered 
Sugar.  Utilization  of  the  By-products.  Yellow 
Sugar.  Maple  Sugar.  The  Date-palm.  Sorghum. 
Cane  Syrup.  Adulteration  of  Sugar. 

Chapter  XI — Alcoholic  Beverages   153-164 

Classification.  Historical.  Fermentation.  The  Brew- 
ing of  Beer.  Raw  Material.  Processes  in  Manu- 
facture. Composition  of  Beer.  Adulteration.  Sub- 
stitution. Kinds  of  Beer. 

Chapter  XII — Alcoholic  Beverages   (Continued) 1 65- 175 

The  Wine  Industry.  Processes  in  the  Manufacture 
of  Still  Wine.  Improving  Wines.  Champagne. 
Sophisticated  Wines.  Adulteration.  By-products. 
Distilled  Liquors.  Distillation.  Bonded  Whiskey. 
Cider.  Vinegar.  Adulteration.  Koumiss. 

Chapter  XIII— Fats    : 176-186 

Extraction.        Purification.        Butter.        Composition. 


CONTENTS  Vll 

Processes  in  Butter-making.  Renovated  Butter. 
Oleomargarine.  Material  Used.  Processes  in  Manu- 
facture. Olive  Oil.  Processes  in  Manufacture. 
Adulteration.  Cottonseed  Oil.  Peanut  Oil. 

Chapter  XIV — Animal  Foods   187-200 

Meat.  The  Physical  Structure  and  Chemical  Con- 
stitution. Meat  Inspection.  Reasons  for  Cooking 
Meat.  Changes  in  Cooking.  Beef  Extracts.  Beef 
Juices.  Internal  Organs.  Fish.  Nutritive  Value. 
Edible  Portion.  Adulteration.  Shellfish.  Eggs. 
Physical  Structure.  Composition  of  the  Shell. 
Methods  of  Preservation.  -Composition  of  the  Egg. 

Chapter  XV — The  Packing  House 201-209 

Historical.  Growth  and  Breadth  of  the  Industry. 
Processes  in  the  Packing  House.  Inspection  and 
Slaughtering.  Use  of  By-products.  Hides.  Fat. 
The  Feet.  Bone  Products.  Tankage.  Blood.  Mix- 
ing Fertilizers.  Glue  and  Gelatin.  Canning  of 
Meat.  Beef  Extracts.  Sausages.  Minor  Products. 

Chapter  XVI — Milk    210-223 

Source.  Composition.  Importance  of  the  Milk 
Supply.  Diseases  from  Milk.  Necessity  for  Clean- 
liness. Safeguarding  the  Milk  Supply.  Our  Duty 
to  the  Producer.  Testing  of  Milk.  Sterilization. 
Pasteurization.  Certified  Milk.  Modified  Milk. 

Chapter  XVII — Milk  Products 224-234 

Condensed  Milk.  Evaporated  Milk.  Concentrated 
Milk.  Milk  Powders.  By-products  of  the  Butter 
Industry.  Skim  Milk.  Dried  Casein.  Milk  Sugar. 
Buttermilk.  Artificially  Soured  Milk.  Cheese.  His- 
torical. Composition.  Cheesemaking.  Adulteration. 

Chapter  XVIII — Preservation  of  Foods 235-246 

Classification.  Drying.  Cooling.  Sterilization  and 
Exclusion  of  Air.  Sugaring.  Salting.  Smoking. 
Use  of.  Fats  and  Oils.  Use  of  Spices.  Alcohol. 
Use  of  Preservatives.  Artificial  Sweetening.  Arti- 
ficial Coloring. 


Vlll  CONTENTS 

Chapter  XIX — The  Canning  Industry 247-254 

(Historical.  Process.  Success  of  Canning  Fruits  and 
Vegetables.  Meat  Products.  Containers.  Advan- 
tages and  Disadvantages  of  Glass.  Advantages  and 
Disadvantages  of  Tin.  Adulteration. 

Chapter  XX — Tea,  Coffee  and  Coco 255-276 

Historical.  Cultivation  of  the  Tea  Plant.  General 
Classification.  Processes  in  Manufacture.  Black 
Tea.  Green  Tea.  Adulteration.  Tea  as  a  Beverage. 
General  Rules  for  Tea-making.  Composition  of  the 
•Beverage.  Coffee.  Historical.  The  Coffee  Plant. 
Cultivation.  Processes  in  Manufacture.  Adultera- 
tion. Coffee  as  a  Beverage.  Coffee  Extracts.  Coco. 
Historical.  Cultivation.  Processes  in  Manufacture. 
Preparation  of  Chocolate.  Preparation  of  Coco. 
Adulteration.  As  a  Beverage. 

Chapter  XXI — Spices  and  Condiments 277-287 

Salt.    Spices.   Uses.    Spices  as  Preservatives.   Vanilla. 

Pepper.     Mustard.     Cinnamon   and    Cassia.     Cloves. 

Allspice.     Nutmeg  and  Mace.     Ginger.     Adulteration. 

Vinegar.. 

Bibliography    288-294 

Index    295- 


INTRODUCTION. 


In  regard  to  the  production  and  manufacture  of  our  food 
material,  there  is  a  prevalent  ignorance  among  woman  to-day 
which  is  a  marked  contrast  to  the  knowledge  possessed  on  this 
subject  by  the  old-fashioned  housekeeper.  The  reason  for  this 
can  readily  be  seen  for  in  the  early  days,  and  in  fact  until  com- 
paratively recent  years,  agriculture  was  very  near  the  home  and 
in  the  majority  of  cases  the  housewife  herself  was  the  manufac- 
turer. The  spinning-wheel,  now  so  highly  prized  as  a  memento 
of  the  olden  times,  testifies  to  the  fact  that  our  grandmothers 
knew  full  well  how  to  manufacture  the  clothing  for  their  fami- 
lies. A  closer  look  at  these  same  days  will  show  that  they  knew 
equally  well  how  to  prepare  many  food  products  and  materials 
needed  for  household  work. 

As  civilization  has  advanced  the  tendency  toward  the  massing 
together  of  our  population  in  towns  and  cities  has  gradually 
changed  greatly  the  home  life  of  the  people.  Agriculture  no 
longer  is  carried  on  in  proximity  to  the  home,  and  large  com- 
mercial establishments  remote  from  the  household  now  do  the 
work  that  at  one  time  was  the  daily  duty  of  the  housewife. 
Many  such  examples  can  be  found.  In  our  later  study  of  the 
history  of  milling,  we  will  find  that  among  all  primitive  people, 
the  woman  was  the  miller,  grinding  each  day  the  grain  she  was 
to  make  into  bread;  the  preparation  of  the  meal  and  breadmaking 
were  practically  one  operation.  Later  on  in  the  history  of  the 
human  family,  the  making  of  meal  and  flour  passed  into  the 
hands  of  the  village  miller,  who  ground  the  grain  for  the  pro- 
ducers of  his  neighborhood,  who  in  turn  bought  their  sack  of 
flour  directly  from  him.  As  this  business  grew  in  size  it  grad- 
ually was  moved  further  and  further  from  the  home,  until  the 
average  housekeeper  of  to-day  knows  little  of  the  mighty  indus- 
try that  is  preparing  the  flour  for  her  use.  More  and  more  each 
year,  we  find  that  the  making  of  this  flour  into  bread  is  in  like 
manner  passing  into  the  hands  of  the  modern  manufacturer  of 
bread.  The  old-time  home-made  loaf  of  bread  is  still  found  in 


2  F3OD    INDUSTRIES 

isolated  districts,  but  seldom  in  city  life.  In  the  preparation  of 
alcoholic  beverages  we  again  find  this  marked  change.  As  late 
as  our  own  colonial  days,  every  housewife  knew  how  to  prepare 
beer  and  wines  and  her  reputation  as  a  homekeeper  was  judged 
as  much  by  the  beer  that  she  could  brew,  as  by  the  loaf  of  bread 
that  she  could  bake.  The  curing  of  meat  and  fish  by  salting  and 
smoking,  the  drying  of  fruits  and  vegetables  now  are  known  only 
to  the  housekeeper  in  isolated  sections  of  our  country,  for  the 
city  woman  must  depend  on  the  manufacturer's  supply.  Even 
the  preservation  of  our  food  by  canning  is  rapidly  passing  into 
the  hands  of  the  canning  industry. 

These  marked  changes  in  our  food  preparation  have  brought 
new  types  of  foods  on  the  market  and  have  greatly  increased  the 
variety.  To  the  modern  housekeeper,  they  have  brought  both 
advantages  and  disadvantages. 

Advantages. — I.  There  has  been  a  great  lessening  of  household 
drudgery,  giving  an  opportunity  for  broader  interests  and  for 
more  recreation  than  was  known  to  our  grandmothers. 

II.  In  the  majority  of  cases  better  products  can  be  obtained 
for  the  methods  of  preparation  used  by  the  housekeeper  were 
necessarily  very  crude.    Manufacturers  for  financial  reasons  must 
give  much  study  to  their  particular  industry  and  new  and  better 
methods  are  constantly  being  sought.     This  has  led  to  improved 
sanitary  conditions  and  a  standardizing  of  the  quality  of  the 
product. 

III.  In  recent  years  there  has  been  a  great  extension  of  the 
open  season ;  fresh  fruits  and  vegetables  are  nowr  quite  common 
in  the  city  markets  the  year  round.    The  variety  of  food  has  been 
also  increased  by  canning. 

IV.  Great  improvements  have  taken  place  in  the  science  of 
agriculture  leading  gradually  to  the  raising  not  only  of  better 
products  but  to  the  increase  in  the  area  of  production,  of  prod- 
ucts which  formerly  were  obtainable  only  from  a  limited  section, 
as  oranges  and  other  fruits,  sugar  from  the  beet  and  wines. 

V.  New  and  improved  methods  of  food  preservation  have  been 
largely  studied  as  canning  and  the  use  of  cold  storage. 


FOOD    INDUSTRIES  3 

VI.  The    co-operation    with    scientists    has    led   to    protection 
against   certain   diseases   as   tuberculosis    from   meat   and   milk, 
typhoid  from  the  oyster,  trachina  from  pork,  etc. 

VII.  Articles  of  food  are  now  put  up  in  better  and  more  sani- 
tary packages  and  better  packing  material  is  being  used. 

Disadvantages. — I.  The  cost,  of  living  has  been  greatly 
increased. 

a.  Foods  may  be  roughly  divided  into  permanent  and  perish- 
able material.     Among  the  permanent   foods,  the  cost  has   de-- 
creased, as  sugar  and  flour.     The  great  advance  in  price  of  our 
food  material  is  found  entirely  in  the  perishable  foods.     Such 
material  is  now  often  brought  from  a  long  distance,  thus  adding 
cost  of  freight  and  many  times  the  cost  of  preservation  during 
transportation.     The  many  hands  through  which  food  material 
must  pass  also  increases  the  cost. 

b.  Packages  are  sometimes  used  without  enhancing  the  value. 
Many  times  this  means  that  the  actual  weight  of  the  food  material 
is  less  than  the  housekeeper  supposes  as  the  weight  of  the  box 
or  package  is  included. 

c.  The  open  market  has  led  to  expensive  tastes.    Luxuries  look 
attractive  and  the  cost  is  great  where  such  products  have  been 
brought  from  a  distance. 

II.  The  women  of  our  country  represent  about  90  per  cent, 
of  the  retail  buyers  in  food  products.  A  lack  of  knowledge  and 
many  times  of  interest  have  led  to  great  deception  on  the  part  of 
some  manufacturers. 

a.  Until  the  Pure  Food  Law  went  into  effect,  there  was  a  great 
amount  of  adulterated  material  put  on  the  market  and  preserva- 
tives were  most  freely  used. 

b.  The  substitution  of  cheaper  products  with  intent  to  deceive 
the  purchaser  was  also  a  common  practice.     Butter  substitutes 
were  sold  as  butter,  cottonseed  oil  as  olive  oil,  apple  jelly  as 
currant,  canned  herring  as  sardines,  potted  veal  for  chicken,  and 
the  like. 

c.  Following  these  evils  there  gradually  crept  in  the  custom  of 
printing  misleading  statements  on  the  outside  wrappers  as  to  the 


4  FOOD    INDUSTRIES 

effect  and  food  value  of  the  contents.  Much  advertising  was 
done  also  giving  these  false  impressions. 

Had  the  modern  housekeeper  possessed  the  knowledge  of  her 
grandmother  as  to  the  production  and  manufacture  of  food 
material  she  was  buying,  manufacturers  would  not  have  found 
it  advantageous  to  practice  such  frauds  for  so  long  a  period. 

The  United  States  Government  has  for  many  years  been  study- 
ing and  experimenting  along  these  lines,  and  bulletins  have  been 
printed  which  can  be  procured  free  or  at  a  very  small  cost,  yet 
comparatively  few  housekeepers  seek  such  information.  This 
lack  of  knowledge  and  interest  led  the  faculty  of  the  School  of 
Practical  Arts,  Columbia  University,  to  introduce  many  years 
ago,  into  its  domestic  science  course,  a  study  of  the  manufacture 
of  food  material,  hoping  that  a  more  extended  knowledge  of  this 
subject  would  lead  to  greater  interest  and  more  intelligent  buying 
on  the  part  of  the  modern  housekeeper. 

In  connection  with  the  following  course  .of  lectures,  excursions 
should  be  taken  as  frequently  as  possible  to  manufacturing  estab- 
lishments, where  processes  and  methods  can  be  studied  and  sani- 
tary conditions  noted.  Wherever  such  excursions  are  not  prac- 
tical, illustrative  material  and  demonstrations  should  be  most 
freely  used,  accompanied  whenever  possible  by  the  use  of  the 
stereopticon  and  moving  picture  slides. 


CHAPTER  I. 


FOOD  PRINCIPLES. 

Food  principles  are  types  of  chemical  compounds  differing  in 
exact  composition  but  of  equal  energy  value.  They  are  reducible 
to  similar  forms  by  the  process  of  digestion. 

Functions. — Food  has  two  important  functions :  first,  to  supply 
tissue  for  the  growth  of  the  young  child,  and  since  life's  processes 
are  continually  breaking  down  this  body  structure,  to  supply 
needed  material  for  its  repair ;  second,  to  furnish  the  organism 
with  fuel  which  in  burning  gives  power  to  carry  on  life's  activi- 
ties;  the  heat  produced  is  utilized  to  maintain  the  temperature 
necessary  to  the  organism. 

Conservation  of  Energy. — Locked  up  in  the  resources  of  nature 
is  a  vast  wealth  of  energy.  Man  has  only  to  seize  this  energy  and 
convert  it  into  a  form  which  he  needs.  Thus  we  find  wood,  coal, 
petroleum  and  natural  gas  being  utilized  to  give  heat  and  light. 
Should  the  energy  be  contained  in  a  compound  which  can  be 
finally  assimilated  by  the  human  body  he  can  accept  it  as  a  food. 

Elements  in  Food. — Nature  does  not  always  give  us  these 
foods  in  a  simple  state ;  many  of  them  are  quite  complex  in  their 
nature.  When  analyzed,  however,  it  has  been  found  that  even 
the  complicated  forms  are  composed  of  the  most  common  ele- 
ments as  carbon,  hydrogen,  oxygen,  nitrogen,  with  a  small  amount 
of  sulphur,  phosphorus,  iron,  calcium,  etc. 

Food  Principles. — Although  these  elements  may  be  differently 
combined,  they  can  be  divided  into  groups  which  are  called  the 
five  food  principles : 

1.  Water  composed  of  hydrogen  and  oxygen. 

2.  Carbohydrates  composed  of  carbon,  hydrogen  and  oxygen. 

3.  Fats  composed  of  carbon,  hydrogen  and  oxygen. 

4.  Protein  composed  of  carbon,  hydrogen,  oxygen,  nitrogen, 

sulphur,  generally  phosphorus,  sometimes  iron,  etc. 

5.  Mineral  matter — as  sodium,  potassium,  calcium,  magnesium, 

iron,  sulphur,  phosphorus,  chlorine,  and  minute  quanti- 
ties of  iodine,  fluorine  and  silicon. 


6  FOOD    INDUSTRIES 

Examples  of  Each  Group. — Among  the  carbohydrates  we  find 
such  well-known  foods  as  starch,  sugar,  cereals  and  vegetables. 
Fats  may  appear  in  different  forms  as  liquids,  semi-solids  and 
solids,  represented  by  olive  oil,  butter  and  suet.  Protein  in  its 
most  concentrated  form  occurs  in  the  white  of  egg,  large  amounts 
being  also  found  in  meat,  fish,  cheese,  eggs  and  milk.  Usually 
we  look  to  animal  life  for  our  protein  supply,  although  it  occurs 
also  in  the  vegetable  kingdom,  relatively  large  amounts  being 
found  in  beans,  cottonseed  meal,  peas,  lentils  and  smaller 
amounts  in  wheat,  maize  and  other  cereals.  The  vegetable  king- 
dom supplies  mankind  with  most  of  his  carbohydrate  food, 
animal  carbohydrate  occurring  only  in  such  forms  as  milk-sugar, 
glycogen  and  glucose.  Fat  occurs  frequently  in  both  animal  and 
vegetable  life. 

Function  of  Each  Group. — Although  all  of  the  food  principles 
have  nutritive  value  each  group  has  its  own  special  function. 
This  work  may  be :  first,  directly  building  tissue ;  second,  giving 
energy  and  heat ;  third,  making  it  possible  for  other  groups  to 
carry  out  their  special  function.  The  great  work  of  building 
tissue  and  gradually  repairing  it  as  it  wears  away  can  be  per- 
formed by  protein  and  inorganic  matter,  water  always  assisting 
in  this  work.  The  other  food  principles  cannot  build  tissue; 
therefore,  protein,  mineral  matter  and  water  are  absolutely  essen- 
tial to  life.  None  of  the  three  is  alone  sufficient.  The  work  of 
producing  energy  is  done  by  all  the  food  principles,  although  only 
in  a  very  limited  sense  by  mineral  matter. 
Tissue  Builders: 

Protein. 

Mineral  matter. 

Water. 
Energy  Producers : 

Protein. 

Carbohydrate. 

Fat. 

Protein  alone  is  able  to  fulfil  both  of  these  functions  of  foods ; 
for  this  reason  it  is  of  vast  importance  in  the  diet.  Without 


FOOD   INDUSTRIES  7 

protein  life  is  impossible  for  any  length  of  time  for  the  wear  and 
tear  on  the  tissue  must  be  replaced.  With  protein  assisted  by 
water  life  can  be  maintained  for  some  time.  In  many  classifica- 
tions only  four  food  principles  are  given,  protein,  carbohydrate, 
fat  and  mineral  matter,  water  being  omitted.  It  is  claimed  that 
water  cannot  build  tissue,  neither  does  it  supply  the  organism 
with  fuel  from  which  to  produce  heat  and  energy;  therefore,  it 
cannot  be  called  a  food  principle. 

Importance  of  Water. — Whether  this  statement  be  true  or  not, 
tissue  building  and,  in  fact  most  of  life's  processes,  cannot  go  on 
without  the  presence  of  water.  Blood  is  the  great  carrier  of  the 
system  and  there  water  is  essential.  It  acts  as  an  eliminator, 
washing  out  the  tissues  and  carrying  away  waste  matter  loitering 
there.  Water  acts  as  a  chemical  agent.  It  has  the  power  of  dis- 
solving substances,  is  essential  to  hydrolysis  and  can,  therefore, 
assist  in  bringing  about  such  chemical  changes  that  otherwise 
useless  food  can  eventually  become  part  of  the  living  organism. 
Its  services  to  all  forms  of  life  cannot  be  over-estimated. 
Whether  we  regard  it  as  merely  a  chemical  agent  or  as  a  true 
food,  next  to  the  atmosphere  we  breathe  it  is  the  most  essential 
thing  in  life. 

CARBOHYDRATES. 

In  order  to  obtain  the  necessary  amount  of  heat,  and  muscular 
energy  it  is  necessary  to  supply  the  body  with  fuel.  This  work 
is  done  largely  by  the  carbohydrates,  a  group  containing  carbon, 
hydrogen  and  oxygen.  The  hydrogen  and  oxygen  occur  in  the 
same  proportion  as  in  water,  and  the  carbon  as  six  or  some  mul- 
tiple of  six  in  most  of  those  forms  utilized  as  human  food.  The 
carbohydrates  owe  their  value  as  a  fuel  very  largely  to  the  carbon 
which  on  oxidation  gives  off  much  heat  energy.  They  are  found 
in  a  large  variety  of  foods:  flour,  meal,  cereals,  sugar,  starch, 
vegetables  and  fruits.  Sometimes  they  appear  in  simple  forms 
which  can  easily  be  made  use  of  by  the  organism ;  at  other  times 
so  complicated  is  the  molecule,  that  only  after  many  chemical 
changes  do  they  assume  a  form  simple  enough  to  pass  through 
the  membrane  of  the  intestines.  From  the  standpoint  of  nutri- 


8  FOOD    INDUSTRIES 

tion  the  alimentary  canal  must  be  looked  upon  as  outside  the 
body,  the  lining  of  this  canal  being  the  outer  coating  of  the  body 
proper.  All  foods,  therefore,  must  be  reduced  to  chemical  com- 
pounds which  are  capable  of  passing  through  the  walls  of  the 
intestines  before  assimilation.  The  most  important  properties 
for  assimilation  are  solubility  and  osmotic  power.  Those  carbo- 
hydrates which  cannot  be  reduced  to  forms  having  these  proper- 
ties cannot  be  utilized  as  food. 

Classification.— 

I.  Monosaccharids  or  Simple  Sugars,  C0H1:,(  )(i. 

Glucose  or  grape  sugar,  formerly  called  dextrose. 
Fructose  or  fruit  sugar,  formerly  called  levulose. 
Galactose. 

II.  Disaccharids  or  Double  Sugars,  G12H22O11. 
Sucrose  or  sugar. 
Maltose. 

Lactose  or  milk  sugar. 

III.   Polysaccharids  or  Complex  Sugars,  (C6H10O5),,. 
Cellulose. 
Starch. 
Dextrin. 
Glycogen. 

Formation  of  Carbohydrates. — The  monosaccharids  or  simple 
sugars  are  built  up  in  the  leaf  of  the  plant,  by  the  absorption  of 
the  carbon  dioxide  and  water  of  the  atmosphere.  With  the 
assistance  of  the  chlorophyll  cells  of  green  plants  and  the  energy 
of  the  sun's  rays,  the  following  compounds  are  formed  in  the 
leaf: 

H2O  +  CO2—  HCHO  +  O, 
6HCHO  —   C6H12O6 

Glucose,  C6H12O6,  is  soluble  and  diffusible  so  it  can  pass  from 
one  part  of  the  plant  to  another.  When  this  material  is  to  be 
stored  as  reserve  food  for  the  plant,  water  is  withdrawn  and 
starch,  an  insoluble  and  colloidal  compound,  is  formed: 

«C6HW06'—  (C6H1005)«  +  H20. 


FOOD    INDUSTRIES  9 

Occurrence. — Glucose  is  an  important  simple  sugar  widely  dis- 
tributed in  nature,  and  is  found  to  a  great  extent  in  the  same 
plants  as  contain  sucrose.  Grapes  contain  about  20  per  cent., 
hence  the  common  name  grape  sugar.  It  occurs  also  in  sweet 
corn  and  most  of  the  garden  vegetables  and  fruits.  In  animal 
life  it  occurs  in  small  quantities  in  the  blood,  o.i  per  cent.,  where 
it  is  constantly  being  burned  to  produce  energy.  Where  the  body 
has  more  or  less  lost  the  power  to  burn  glucose  as  with  diabetes, 
it  accumulates  and  is  finally  eliminated  by  the  kidneys. 

Fructose  is  usually  found  associated  with  glucose.  It  occurs 
in  the  juices  of  sweet  fruits,  the  largest  amount  being  found  in 
honey. 

Galactose  is  not  found  in  nature.  It  occurs  only  in  the  splitting 
of  lactose  or  milk-sugar  during  the  process  of  digestion. 

Sucrose  is  the  most  important  of  the  sugars  as  it  is  the 
ordinary  crystallized  sugar  of  commerce.  It  is  found  widely 
distributed  in  the  vegetable  kingdom  in  the  fruit  and  juices  of 
a  variety  of  plants,  many  times  occurring  in  relatively  large 
amounts  as  in  the  pineapple,  strawberry  and  carrot.  It  is  ex- 
tracted commercially  from  the  sugar  cane,  the  sugar  beet,  the 
sorghum  cane,  the  date  palm  and  the  sugar  maple. 

Maltose  never  occurs  in  nature  in  large  quantities.  It  is  the 
carbohydrate  which  is  formed  from  starch  during  the  germina- 
tion of  seeds.  As  a  commercial  product  it  plays  an  important 
part  in  the  brewing  industry,  in  the  so-called  malted  breakfast 
foods  and  in  malted  milk. 

Lactose  occurs  in  the  milk  of  all  mammals  usually  from  3  to 
7  per  cent.  It  is  the  most  abundant  of  the  animal  carbohydrates. 

Cellulose  or  crude  fiber  constitutes  the  framework  of  all  vege- 
table tissue,  so  we  find  it  widely  distributed  throughout  the 
vegetable  kingdom.  It  occurs  in  wood,  linen,  cotton,  hemp,  flax 
and  paper.  Much  of  our  food  as  cereals,  vegetables  and  fruit 
contain  cellulose,  but  as  it  cannot  be  made  soluble  in  the  organism 
it  has  no  food  value.  Other  forms  of  life  can  utilize  it,  however, 
and  we  find  it  serving  as  food  for  insects  and  bacteria. 

Starch  as  it  is  found  in  nature  is  also  insoluble  and  indiffusible. 


10  FOOD   INDUSTRIES 

but  here  we  find  a  carbohydrate  which  can  be  changed  to  a 
simpler  form  within  the  alimentary  canal.  It  is  found  largely 
in  vegetables  where  it  is  stored  as  food  for  the  plant. 

Dextrin  or,  as  it  is  commonly  called  gum,  is  formed  from 
starch  by  the  process  of  hydrolysis.  In  nature  it  occurs  in  ger- 
minating cereals. 

Glycogen  is  often  spoken  of  as  the  animal  starch,  although  it 
more  closely  resembles  dextrin.  It  is  found  to  the  largest  extent 
in  shell-fish,  especially  the  scallop.  It  is  also  abundant  in  the 
muscle  and  liver  of  both  higher  and  lower  animals,  where  it  is 
stored  and  ultimately  utilized  as  a  source  of  muscular  energy. 

Important  Properties. — Among  the  most  important  properties 
of  the  carbohydrates  are  found  solubility,  diffusibility,  hydrolysis,  • 
crystallization  and  action  on  polarized  light. 

Hydrolysis. — This  important  property  occurs  repeatedly  in  the 
changing  of  complicated  forms  of  food  material,  to  such  simple 
forms  that  they  can  be  utilized  by  the  organism.  It  has  been 
defined  by  Alexander  Smith  as  "A  double  decomposition  involv- 
ing water"  and  by  other  well-known  chemists  as  "A  simplification 
with  absorption  of  water."  Changes  taking  place  during  hydroly- 
sis are  always  brought  about  by  certain  agents,  which  do  not 
themselves  enter  in  any  way  into  the  compound  being  formed. 
These  agents  may  be  heat,  dilute  acid,  bacterial  action,  enzyme 
action,  etc.  The  action  always  takes  place  in  the  presence  of 
water,  both  the  water  molecule  and  the  complex  carbohydrate 
molecule  breaking  down  to  form  a  new  carbohydrate  molecule 
in  which  the  hydrogen  and  oxygen  appear  in  the  proportion  as 
in  water. 

2C6H1005  +  H20  ^  C,2H22On, 

Starch  Maltose 

C12H2IOn  +  H20  ^  2C6H,A. 

Maltose  Glucose 

Sucrose  is  a  double  sugar.  When  it  breaks  down  under  the 
influence  of  a  catalytic  agent  it  yields  two  simple  sugars  as 

C12H220U  -f  H20  ^  C6H1206  glucose, 
C6H12O6  fructose. 


FOOD   INDUSTRIES  II 

A  special  name  has  been  given  to  these  two  molecules,  glucose 
and  fructose.  They  are  called  invert  sugar.  This  name  has  been 
given  to  them  on  account  of  their  peculiar  behavior  toward 
polarized  light.  Before  hydrolysis  a  sugar  solution  will  rotate 
the  plane  of  polarized  light  to  the'  right,  after  hydrolysis  to  the 
left,  hence  the  name  invert  sugar  and  the  term  inversion. 

Hydrolysis  also  occurs  in  the  digestion  of  fats  and  proteins. 

FATS. 

Composition. — True  fats  are  composed  of  the  elements  carbon, 
hydrogen  and  oxygen.  Little  was  known  of  how  these  elements 
were  combined  in  the  formation  of  fats,  until  the  investigation 
by  Chevreul  in  the  early  part  of  the  nineteenth  century.  He  dis- 
covered that  they  were  essentially  salt-like  bodies  formed 
together  with  water  by  the  combination  of  an  acid  and  a  base. 
With  the  exception  of  some  of  the  waxes  the  base  is  always  the 
same,  the  triatomic  alcohol  glycerine,  C3H5(OH)3.  The  acid 
usually  belongs  to  a  series'  termed  fatty  acids  and  varies  accord- 
ing to  the  fat.  The  three  most  common  fatty  acids  are  oleic, 
palmitic  and  stearic  acid.  Unless  a  fat  or  oil  contains  both 
glycerine  and  a  fatty  acid,  it  is  not  a  true  fat. 

C3H5(OH)3  +  3C17H3;{COOH  ^  C3H5(C18H33O3)3  +  3H2O, 
Glycerine  Oleic  acid  Olein  Water 

C3H5(OH)3  +  3C15HSICOOH  -  C3H5(C16H31O2)3  +  3H2O, 
Glycerine  Palmitic  acid  Palmitin  Water 

C3H5(OH)3  +  3C17H35COOH  ^  C3H5(C18H35O2):i  +  3H2O. 
Glycerine  Stearic  acid  Stearin  Water 

Two  or  more  of  these  fatty  acids  are  generally  present  in  all 
fats — mixed,  not  chemically  combined.  They  differ  in  their 
physical  nature.  Olein  is  liquid  at  ordinary  temperature  and 
whenever  this  acid  predominates,  the  fat  appears  in  the  liquid 
form  as  in  olive  oil.  Palmitin  is  semi-solid;  it  predominates  in 
butter  and  lard  and  is  the  largest  part  of  the  human  fat.  When- 
ever stearin  is  present  in  a  relatively  large  amount,  the  fat  is  a 
solid  as  in  suet  and  tallow. 

Occurrence. — Fats  are  found  widely  distributed  throughout 
both  the  animal  and  vegetable  kingdoms.  In  plants  the  percent- 


12  FOOD    INDUSTRIES 

age  varies  to  a  great  extent,  approximately  i  per  cent,  being 
found  in  barley  and  67  per  cent,  in  Brazilian  nuts.  Fat  usually 
occurs  in  inverse  ratio  to  the  starch.  It  is  often  difficult  to 
extract  as  it  is  deposited  throughout  the  plant;  no  part  seems  to 
be  entirely  wanting  in  fat.  In  animal  life  fats  are  present  in  all 
tissues  and  organs  and  in  all  fluids,  with  the  exception  of  the 
normal  urine.  Large  quantities  are  found  in  the  abdominal 
cavity  surrounding  the  kidneys,  and  beneath  the  skin  of  marine 
animals  or  those  living  in  cold  climates.  Being  present  often  in 
large  quantities,  it  is  very  easy  to  extract. 

Properties. — The  most  important  properties  are  solubility, 
change  of  state,  crystallization,  drying  and  non-drying,  emulsifi- 
cation  and  saponifkation. 

Solubility. — Fats  are  soluble  in  gasolene,  ether,  chloroform, 
warm  alcohol  and  carbon  disulphide.  These  solvents  may  be 
used  for  cleansing  purposes,  for  extraction  and  removal  of  grease 
stains. 

Change  of  State. — All  fats  have  a  definite  melting  point.  They 
exist  as  liquids,  semi-solids  and  solids  according  to  the  tempera- 
ture. This  property  is  taken  advantage  of  in  the  extraction  of 
fats  and  as  a  means  of  identification. 

Crystallization. — All  fats  are  highly  crystalline.  They  form 
definite  crystals  and  can  be  readily  identified  under  a  microscope. 
This  has  been  of  great  value  in  detecting  adulteration. 

Drying  and  Non-drying. — Certain  oils  are  oxidized  when 
exposed  to  the  air  and  are  converted  into  thick  gummy  masses. 
These  drying  oils  when  applied  in  thin  layers  on  a  surface  form 
a  dry,  hard,  transparent  film.  They  are  used  extensively  in 
paints  and  varnishes  as  linseed  oil.  Some  oils  such  as  cotton- 
seed possess  this  property  to  a  limited  extent,  while  others  as 
olive  oil  show  no  sign  of  drying  even  when  exposed  to  the  air 
for  an  indefinite  period. 

Eniulsification. — Fats  can  be  broken  up  in  small  globules  by 
mechanical  agitation.  If  these  globules  can  be  coated  with  a  sub- 
stance which  will  prevent  them  from  running  together,  they  will 
remain  in  suspension.  Egg  albumin  is  very  frequently  the  agent 


FOOD   INDUSTRIES  13 

used  iii  making  an  emulsion ;  example — mayonnaise  dressing. 
This  property  is  taken  advantage  of  in  soap-making  and  in  the 
cleansing  of  fatty  material  by  means  of  soap.  It  always  occurs 
as  an  early  stage  in  the  digestion  of  fats. 

Saponification. — The  process  of  splitting  a  fat  into  its  con- 
stituents, fatty  acid  and  glycerine,  is  termed  saponification.  It 
may  be  brought  about  by  such  agents  as  heat,  mechanical  agita- 
tion, bacterial  action  and  use  of  an  alkali.  Saponification  always 
occurs  in  the  digestion  of  fats  and  in  the  process  of  soap-making. 


PROTEINS. 

Composition. — The  proteins  are  very  complex  compounds 
differing  greatly  in  composition  and  properties,  but  all  are  of 
high  molecular  weight.  They  are  composed  of  carbon,  hydrogen, 
oxygen,  nitrogen,  sulphur  usually  phosphorus,  sometimes  iron, 
lime,  etc.  As  nitrogen  compounds  they  play  an  important  part 
in  human  nutrition,  for  they  are  essential  to  the  growth  of  the 
living  cells  which  make  up  the  tissue. 

Classification. — The  following  is  a  modification  of  the  classifi- 
cation recommended  by  the  American  Physiological  Society  and 
the  American  Society  of  Biological  Chemists. 


(  Simple 


f  Albumins 
Globulins 
Glutelins 
Alcohol  solubles 
Albuminoids 


Nucleoprotein 
Proteins "I   Conjugated.  .,   phospl]oprotdn 


Non-protein 


I  Derived 


Extractives 

Amides 

Amino-acids 


f  Coagulated  proteins 
Primary  ....    I   Meta  proteins 
|   Proteans 

j   Proteoses 

Secondary  . .    |    Peptones 
I   Peptids 


14  FOOD    INDUSTRIES 

Occurrence. — Albumin  is  found  in  both  plant  and  animal  life. 
It  occurs  most  abundantly  in  the  white  of  egg,  where  it  coagu- 
lates on  being  cooked  in  boiling  water  and  becomes  a  hard  white 
mass.  It  appears  in  milk  as  lact-albumm,  in  egg  as  ova-albumin, 
in  fluids  of  the  animal  body  such  as  muscle  and  blood  as  serum 
albumin.  A  small  proportion  of  the  .protein  of  plant  life  occurs 
as  albumin. 

Globulin  is  very  similar  to  albumin,  but  differs  from  it  in  solu- 
bility. It  occurs  in  both  plant  and  animal  life,  but  is  far  more 
abundant  and  wide-spread  in  plant  tissue.  Globulin  is  found  in 
large  proportion  in  hemp-seed,  flax-seed,  and  in  the  seeds  of  the 
legumens.  Animal  globulin  occurs  in  muscle  and  blood. 

Glutelins  are  nitrogenous  compounds  found  in  the  cereal  grains. 
The  most  familiar  example  is  the  glutenin  of  wheat.  Alcohol 
solubles  is  a  form  of  protein  also  found  in  cereals.  The  prin- 
cipal one  is  the  gliadin  of  wheat.  Glutenin  and  gliadin  in  the 
presence  of  water  form  the  well-known  substance  gluten. 

Albuminoids  occur  in  the  skeleton  of  the  body  as  the  connec- 
tive tissue,  bones,  hair,  nails,  hoofs  and  horns.  It  is  that  form 
of  protein  which  yields  gelatin  on  cooking. 

Nucleo-proteins  are  complex  proteins  which  are  believed  to  be 
combinations  of  one  or  more  protein  molecules  with  nucleic  acid. 
They  are  closely  associated  with  the  nuclei  of  cells  in  both  plant 
and  animal  life  and  occur  most  abundantly  in  asparagus  tips, 
the  hearts  of  lettuce  and  internal  organs  such  as  liver,  heart, 
kidney  and  pancreas.  In  the  clearage  of  the  molecule  during 
.digestion  true  nucleo-proteins  are  believed  to  yield  uric  acid. 

Phospho-proteins  are  proteins  closely  combined  with  mineral 
matter  as  phosphorus  and  sulphur.  The  most  familiar  examples 
are  the  caseinogen  of  milk  and  the  vitellin  of  egg. 

Protein  Hydrolysis. — As  in  the  carbohydrates,  protein  must 
undergo  hydrolysis  or  a  simplification  before  such  compounds 
can  be  assimilated  by  the  body.  This  change  involves  a  breaking 
down  of  the  protein  molecule,  and  the  taking  up  of  the  elements 
of  water,  under  the  influence  of  agents  such  as  heat,  dilute  acids 
or  alkalis,  bacterial  action  and  enzyme  action.  The  products 


FOOD   INDUSTRIES  15 

formed  are  known  as  derived  proteins.  Primary  derived  pro- 
teins are  those  which  have  been  only  slightly  modified,  secondary 
derived  forms  those  having  been  more  completely  acted  upon  by 
the  hydrolytic  agent.  In  this  way  are  formed  coagulated  proteins, 
meta-proteins,  proteoses,  peptones  and  peptids.  Peptones  for  a 
long  period  were  believed  to  be  the  final  product  of  enzyme  action 
in  digestion,  but  that  action  is  now  believed  to  be  continued  to 
the  amino-acid. 

Extractives. — The  name  extractives  has  been  given  to  a  body 
of  substances  which  can  be  extracted  from  meat  by  the  action 
of  cold  water.  The  most  important  are  creatin  and  creatinin. 
Although  nitrogen  compounds,  they  are  not  capable  of  building 
tissue  and  it  is  believed  that  they  have  little  or  no  food  value. 

Properties. — Among  the  more  important  properties  of  the  pro- 
teins are  solubility,  curdling,  coagulation  and  clotting. 

Solubility. — Albumin  is  soluble  in  cold  water;  gelatin  swells 
and  all  other  proteins  are  insoluble.  All  proteins  are  soluble  in 
dilute  sodium  chloride,  and  with  the  exception  of  albumin,  all  are 
insoluble  in  saturated  sodium  chloride.  All  proteins  are  insoluble 
in  saturated  solutions  of  ammonium  sulphate. 

Curdling. — Curdling  is  a  change  which  occurs  in  connection 
with  conjugated  proteins  such  as  the  caseinogen  of  milk.  It  is 
the  precipitation  of  a  soluble  matter  by  means  of  an  acid,  without 
serious  chemical  change. 

Coagulation. — Albumins  and  globulins  are  made  insoluble  by 
heating  to  about  158°  F.  In  concentrated  solution  such  as  the 
white  of  egg,  solidification  is  caused  throughout  the  mass.  This 
is  a  chemical  change  always  brought  about  by  (i)  heat  some- 
times with  the  aid  of  dilute  acid  or  (2)  the  action  of  alcohol. 

Clotting. — The  term  clotting  is  applied  to  conjugated  proteins, 
when  the  molecule  is  split  by  means  of  an  enzyme  into  two 
simpler  proteins,  for  example, — caseinogen  under  the  action  of 
rennet  is  split  into  casein  and  para  or  pseudo-nuclein. 


CHAPTER  II. 


WATER. 

In  chemical  language  we  speak  of  water  as  a  compound  con- 
taining the  elements  hydrogen  and  oxygen,  in  the  proportion  of 
2  to  i  by  volume  and  I  to  8  by  weight.  Such  a  compound, 
however,  is  never  found  in  nature  and  the  term  as  repeatedly 
used  "pure  water"  is  generally  accepted,  as  meaning  a  water  free 
from  harmful  ingredients  and  which  can,  therefore,  be  utilized 
for  drinking  and  other  household  purposes ;  contaminated  or  pol- 
luted water  contains  material  injurious  to  health. 

Classification  of  Natural  Waters.— 

f  Rain— Contains   very    little   dissolved  solids  but  dust 

and  gases  of  the  atmosphere. 

I.  Atmospheric  •   \ 

j    Snow 

I  Fog 

(  Surface-  Cloudy,  usually  a  large  amount  of 

suspended  matter,  minimum  of  dissolved. 
j   Underground— Clear,  minimum  of  suspended 
i       matter,  maximum  of  dissolved. 

II.  Terrestrial   . .   •{ 

(  Brines — Over  5  per  cent,  soluble  salts. 

I   Sea  water — 3.6  per  cent,  solids. 

1    Mineral— Excess  of   unusual  mineral  matter 

[       and  gases. 

It  is  known  as  the  universal  solvent ;  there  is  scarcely  a  sub- 
stance existing  which  is  not  more  or  less  soluble  in  water.  Hard 
rock  can  be  gradually  worn  away  by  its  action,  and  glass,  one  of 
the  hardest  of  known  substances,  will  gradually  dissolve.  All 
natural  waters  are  found,  therefore,  to  contain  foreign  matter, 
gases  and  solid  material  of  the  atmosphere  and  earth,  either 
dissolved  or  in  suspension.  Sometimes  these  materials  occur  in 
small  amounts,  at  other  times  in  relatively  large  proportions. 
The  nature  and  amount  of  these  gases  and  solids  have  a  con- 
siderable influence  on  the  effect  of  water  to  be  used  for  household 
purposes. 

The  two  great  uses  for  water  in  the  household  are  for  drink- 


FOOD   INDUSTRIES  I/ 

ing  and  for  cleansing  purposes.  There  is  a  standard  to  estimate 
the  purity  of  each.  For  detergent  purposes,  the  amount  of 
mineral  matter  present  plays  an  important  part,  while  for  drink- 
ing, organic  matter  received  directly  or  indirectly  from  sewage 
or  industrial  waste,  constitutes  the  chief  danger.  A  safe  water 
supply  should  be  reasonably  free  from  objectionable  mineral  and 
organic  matter. 

WATER  SUPPLY. 

Historical. — Even  in  remote  antiquity  a  high  value  seemed  to 
have  been  placed  on  an  abundant  water  supply,  and  a  keen  appre- 
ciation existed  of  the  danger  should  such  a  supply  become  con- 
taminated. Settlements  we're  made  and  communities  grew  near 
the  source  of  available  water,  which  many  times  was  looked  upon 
as  a  blessing  bestowed  by  the  gods.  In  districts  where  water  was 
not  abundant  courses  were  constructed  with  much  expenditure 
of  time,  money 'and  labor  to  carry  it  from  a  distance  where  water 
was  found  to  be  pure  and  naturally  plentiful.  Such  courses  were 
built  by  the  ancient  Romans,  where  water  could  proceed  by 
gravity  from  the  distant  mountains  to  the  city  where  great  reser- 
voirs were  built  for  its  storage.  These  reservoirs  were  still  in 
use  during  the  middle  ages  and  the  ruins  to-day  show  how  well 
they  had  been  constructed. 

Methods  of  irrigation  were  used  early  in  the  history  of  the 
world,  for  reservoirs  were  known  to  have  existed  in  Egypt 
before  2,000  B.  C.  They  were  utilized  for  the  purpose  of  receiv- 
ing and  storing  the  surplus  water  during  the  annual  inundation 
of  the  Nile,  the  stored  water  being  used  for  irrigation  during 
seasons  when  the  river  failed  to  reach  the  crops. 

Pumping  as  it  exists  to-day  was  unknown  among  the  ancients, 
but  curious  devices  were  constructed  for  the  elevation  of  water, 
the  ruins  of  which  can  still  be  seen  in  some  parts  of  the  Old 
World.  One  of  the  greatest  curiosities  of  Zurich  is  the  pump 
invented  and  erected  by  a  tin-plate  worker  of  that  city.  It  con- 
sists of  a  hollow  cylinder  like  a  very  large  grindstone  turning  on 
a  horizontal  axis,  and  so  constructed  as  to  be  partly  plunged  in  a 
cistern  of  water.  This  cylinder  is  formed  into  a  spiral  canal  by 


1 8  FOOD    INDUSTRIES 

a  plate  coiled  up  within  it  like  the  main-spring  of  a  watch  in 
its  box. 

Bucket  lifts  in  different  forms  seemed  to  have  been  employed 
the  world  over  from  the  remotest  historical  times.  In  oriental 
countries  an  earthen  pot  attached  to  a  rope  wound  around  a 
windlass  was  used.  Another  form  was  the  scoop-wheel  composed 
of  a  series  of  curved  blades,  terminating  in  a  hollow  axle  into 
which  they  discharged  the  water  scooped  up  by  the  revolution 
of  the  wheel.  A  series  of  buckets  was  sometimes  arranged 
around  a  huge  wheel  which  in  revolving  scooped  up  the  water. 
The  well  sweep  or  bucket  and  balanced  pole,  still  frequently  seen 
in  certain  rural  sections  of  America,  were  water  elevators  of  the 
same  simple  construction  and  principle. 

The  displacement  pump  acting  on  the  principle  that  two  bodies 
cannot  occupy  the  same  space  at  the  same  time  finally  took  the 
place  of  the  bucket  lifts,  and  in  the  sixteenth  century  we  find 
pumps  being  introduced  into  Germany  and  France.  A  little  later 
than  this  Paris  constructed  a  filtering  plant.  Methods  of  puri- 
fication, however,  had  been  studied  much  earlier  for  we  read  that 
400  years  before  the  Christian  Era,  Hippocrates  had  advised 
boiling  and  filtering  drinking  water  should  the  supply  become 
contaminated. 

Classification  of  Potable  Waters.— 

I.  Atmospheric. 
II.  Surface. 

{shallow, 
deep. 

I.  Atmospheric. — Rain  is  the  original  source  of  all  natural 
water.  It  results  from  the  water-vapor  rising  from  the  earth, 
being  condensed  in  the  upper  air  and  again  falling  to  earth.  In 
its  descent  it  to  a  great  extent  purifies  the  atmosphere  by  taking 
up  ammonia,  carbon  dioxide  and  other  soluble  gases  and  by 
washing  down  solid  matter  as  dust,  soot,  industrial  waste  and 
disease  germs.  Near  the  seacoast,  rain  water  is  found  to  contain 
an  appreciable  amount  of  salt  dissolved  in  it.  In  districts  con- 
taining a  number  of  inhabitants  and  factories  rain  water  is  never 


FOOD    INDUSTRIES  1 9 

pure,  for  even  after  prolonged  washing  the  atmosphere  is  still, 
more  or  less  impure.  This  is  not  true  in  the  open  country  for 
there  after  the  air  has  been  purified  by  the  first  rain  that  falls, 
the  water  can  be  collected  and  stored.  This  is  the  purest  form 
of  natural  water  known. 

Stored  rain  should  only  be  used  where  natural  water  cannot 
be  obtained  pure  enough  for  household  purposes.  In  collecting 
rain  the  first  flow  should  run  to  waste,  thus  avoiding  contamina- 
tion by  dirt,  soot  and  other  impurities  washed  from  the  atmos- 
phere and  from  the  surface  on  which  the  water  is  collected. 
Such  water  should  be  filtered  and  great  care  should  be  given  to 
the  storage.  Cisterns  should  be  so  constructed  that  they  will  be 
absolutely  impervious  to  surface  drainage,  -and  so  that  they  can 
easily  be  inspected  and  frequently  cleaned.  The  best  materials 
for  building  are  brick,  stone,  cement  and  slate.  They  should  be 
kept  covered  to  prevent  impurities  from  falling  in  and  to  exclude 
light.  This  will  prevent  the  development  of  low  forms  of  plant 
life. 

II.  Surface  Water. — After  reaching  the  earth  a  portion  of  rain 
water  runs  over  the  ground  to  join  streams  or  larger  bodies  of 
water.     Of  these  waters   lakes   and  rivers   form  an   important 
source  of  our  water  supply.    They  are  known  as  surface  waters. 
The   composition  varies   greatly   according  to   the  character   of 
the  soil  over  which  they  flow.     Should  the  soil  be  rocky  a  por- 
tion of  the  mineral  salts  would  undoubtedly  be  added  to  the 
water,  but  it  would  be  more  or  less  free  from  organic  impurities. 
If  the  water  comes  in  contact  with  swampy  land  it  will  be  very 
rich  in  organic  matter.     The  character  of  these  waters  varies 
also   according  to  the   uninhabited   or   settled   condition   of   the 
locality.     Water  from  a  clear  lake  or  river,  exposed  to  the  sun- 
light and  air,  is  one  of  the  safest  of  water  supplies  in  a  thinly 
populated  region.    Such  bodies  of  water,  however,  become  highly 
polluted  should  they  receive  the  drainage  of  city  or  town  life. 
From  every  point  of  view  running  streams  should  be  kept  free 
from  organic  matter  if  they  are  to  be  used  as  a  water  supply. 

III.  Subsoil  Water. — The  portion  of  rain  water  which  sinks 


2O  FOOD    INDUSTRIES 

into  the  ground  is  known  as  subsoil  or  ground  water.  It  is  used 
as  spring  water  and  shallow  or  deep  well  water.  Subsoil  water 
is  greatly  changed  by  the  character  of  the  earth  through  which 
it  percolates.  It  passes  to  various  depths  according  to  the 
'porosity  of  the  soil  and  the.  arrangement  of  the  strata.  When  it 
reaches  an  impervious  formation  it  accumulates  upon  the  level. 
In  its  descent  to  the  earth  and  again  in  the  soil,  water  dissolves 
more  or  less  carbon  dioxide.  The  presence  of  this  gas  greatly 
assists  in  dissolving  mineral  constituents  of  the  soil.  Thus  we 
find  in  limestone  regions  a  large  amount  of  calcium  carbonate  in 
the  water  supply,  making  the  so-called  hard  water.  This  greatly 
influences  water  to  be  used  for  detergent  purposes.  Rain  water 
percolating  through  the  ground  may  be  changed  also  in  regard 
to  its  purity  as  a  drinking  water.  As  it  enters  the  soil  it  carries 
with  it  whatever  organic  matter  it  has  dissolved  from  the  atmos- 
phere. In  the  upper  layer,  it  again  dissolves  organic  ingredients 
and  becomes  impregnated  with  micro-organisms,  through  the 
agency  of  which  the  organic  matter  undergoes  very  important 
chemical  changes,  gradually  bringing  about  the  purification  of 
the  water.  Water  which  has  percolated  through  the  earth  makes 
a  very  safe'  drinking  supply,  unless  there  is  special  contamination 
due  to  admixture  with  sewer  drainage  which  contains  excretory 
products. 

Shallow  wells  are  much  more  likely  to  be  subject  to  pollution 
of  this  kind.  As  a  rule  deep  wells,  700  feet  or  more,  are  not  apt 
to  be  dangerous,  but  they  are  usually  higher  in  mineral  sub- 
stances than  surface  waters. 

Pollution  of  Wells. — The  chief  danger  to  the  water  supply 
comes  from  earth  closets,  cesspools  and  house-drainages.  To 
avoid  expense  in  construction,  too  often  the  well  and  cesspool 
are  built  comparatively  near  together.  The  bottoms  and  sides 
of  the  old-fashioned  cesspool  were  usually  left  open,  to  allow  the 
house  sewage  to  drain  into  the  surrounding  soil.  Such  condi- 
tions are  a  great  source  of  danger  and  it  is  hoped  that  the  septic 
cesspool  will  be  more  universally  constructed  in  the  future.  In 
the  septic  cesspool,  purification  takes  place  by  bacterial  action  and 


FOOD    INDUSTRIES  21 

the  water  is  not  allowed  to  drain  from  it  until  it  has  been  more 
or  less  freed  from  dangerous  material.  As  regards  location  it  is 
a  common  belief,  that  if  the  well  is  built  on  slightly  higher  ground 
than  the  earth,  closet  or  open  cesspool  there  can  be  no  danger  of 
pollution.  This  is  a  false  impression,  however,  for  it  is  not  so 
much  the  location  that  determines  the  possibility  of  pollution,  as 
the  relative  position  of  the  cesspool  and  the  point  where  the 
water  enters  the  well.  Great  carelessness  has  very  often  been 
shown  in  this  direction  by  the  property  owner,  who  has  little 
regard  for  the  rights  of  his  neighbors  unless  compelled  by  legal 
restrictions.  His  own  water  supply  may  be  carefully  guarded, 
but  the  cesspool  may  be  so  located  as  to  be  a  serious  source  of 
danger  to  neighboring  wells. 

Contamination  of  Public  Supplies. — Much  trouble  has  been 
caused  in  the  past  by  the  same  carelessness  in  regard  to  larger 
supplies,  that  is,  the  location  of  earth  closets  and  cesspools  along 
the  watershed  of  a  public  water  course.  This  utter  disregard  of 
the  rights  of  others  has  been  practiced  by  communities  as  well 
as  individuals.  The  municipal  supply  furnished  to  the  larger 
cities  and  towns  is  often  drawn  from  great  bodies  of  surface 
water,  as  lakes  and  rivers.  Here  there  is  great  opportunity  for 
gross  neglect  of  sanitary  conditions.  Steamships  and  sailing 
vessels  make  a  practice  of  discharging  their  waste  matter  into 
the  water.  Manufacturing  establishments  along  the  banks  add 
to  the  pollution.  The  greatest  danger,  however,  comes  from 
looking  upon  rivers  as  a  convenient  receptacle  for  the  disposal 
of  sewage,  for  as  it  has  often  been  said  by  Mrs.  Richards,  "It  is 
only  after  contamination  with  the  waste  of  human  life  that 
danger  comes  to  other  beings."  Many  epidemics  of  typhoid  in 
the  New  World  and  of  cholera  in  the  Old  World  have  been 
caused  by  using  the  same  body  of  water,  as  a  water  supply  and 
as  a  means  of  disposing  of  refuse.  One  town  may  take  its 
water  from  a  point  above  and  discharge  its  sewage  at  another 
point  below,  a  second  town  farther  down  the  river  takes  the 
already  contaminated  water  for  drinking  purposes,  and  in  its 
turn  discharges  the  sewage  at  another  convenient  point. 


22  FOOD   INDUSTRIES 

Danger  of  Impure  Water. — Hutchison  in  his  "Foods  and 
Dietetics"  tells  us  that  water  is  not  absorbed  by  the  mucous 
membrane  of  the  stomach ;  it  begins  to  flow  into  the  intestines 
at  once.  The  rapidity  with  which  water  passes  through  the 
stomach  causes  it  to  be  a  very  dangerous  vehicle  of  infection, 
for  the  hydrochloric  acid  of  the  gastric  juice  has  not  the  oppor- 
tunity to  act  upon  any  disease  bacteria  which  it  may  contain. 
Once  in  the  intestines  pathogenic  bacteria  find  an  alkaline  medium 
which  is  most  favorable  for  their  growth  and  reproduction.  For 
this  reason  it  is  quoted  that  "Contaminated  water  is  a  more 
obnoxious  carrier  of  disease  than  impure  milk."  Too  much  care 
cannot  be  given  that  our  water  supply  be  above  suspicion. 

While  it  is  the  duty  of  a  city  or  town  to  supply  a  safe  drinking 
water,  to  properly  construct  and  maintain  reservoirs  and  filter- 
ing plants,  and  to  provide  police  surveillance  for  the  water  shed, 
it  is  also  the  duty  of  every  citizen  in  such  a  community  to  cheer- 
fully pay  the  necessary  expense  for  its  maintenance,  and  to  guard 
his  neighbors'  rights  as  his  own.  Education  of  the  people  at 
large  on  this  subject  is  one  of  the  essentials  of  modern  life. 

Diseases  from  Water. — The  presence  of  mineral  matter  quite 
frequently  causes  temporary  intestinal  derangement.  This  is 
more  apt  to  be  true  with  the  visiting  stranger  to  a  community 
than  with  those  accustomed  to  its  use.  The  change  from  a  soft 
to  a  hard  water  disturbs  digestion  and  frequently  causes  con- 
stipation, while  the  change  from  a  hard  to  a  soft  water  may 
bring  about  diarrhoea.  Organic  pollution  from  vegetable  origin 
has  also  been  the  cause  of  many  mild  epidemics  of  diarrhoeal 
troubles.  It  is,  however,  to  the  typhoid  and  cholera  bacteria  that 
the  world  has  owed  its  death  destroying  epidemics. 

Cholera  has  its  home  in  India  and  has  been  largely  kept  alive 
and  scattered  in  all  directions,  by  the  pilgrimages  taken  to  such 
sacred  rivers  as  the  Ganges.  The  pilgrims  from  all  parts  of 
India  travel  in  large  companies  for  hundreds  and  even  thousands 
of  miles.  Exhausted,  filthy  and  many  times  diseased  at  the  end 
of  their  journey,  it  is  their  custom  to  bathe  in  and  drink  of  the 
sacred  waters.  Poorly  fed  and  sheltered  in  the  midst  of  the 


FOOD    INDUSTRIES 


most  insanitary  conditions,  it  is  little  wonder  that  a  cholera 
epidemic  is  soon  started  and  by  returning  pilgrims  is  carried  to 
all  parts  of  the  country.  The  European  and  American  nations 
hear  with  horror  tales  told  of  cholera  in  India,  and  yet  although 
more  enlightened  and  understanding  more  fully  sanitary  condi- 
tions, Europe  and  America  have  repeatedly  been  visited  with 
typhoid  epidemics.  It  has  been  said  that  we  have  not  advanced 
far  in  civilization,  when  we  have  not  yet  learned  as  a  nation  to 
take  care  of  the  excreta  from  our  own  bodies.  Not  until  the 
end  of  the  nineteenth  century  were  authorities  fully  awakened  to 
this  subject,  and  there  is  still  much  work  to  be  done  in  this 
direction. 

PURIFICATION  OF  WATER. 

Public  Methods. — With  the  constant  increase  in  our  population 
and  the  modern  tendency  toward  city  and  town  life,  a  pure  water 


Fig.  i. — Sedimentation  Basin. 

supply  has  become  almost  an  impossibility.  The  most  that  we  can 
demand  now  is  a  safe  water.  Large  sums  of  money  have  been 
used  and  much  experimentation  has  been  carried  on  of  late  years 
to  determine  the  best  methods  of  purification.  Several  very  effi- 
3 


24  FOOD    INDUSTRIES 

cient  methods  have  been  discovered  and  are  now  in  use,  but 
which  is  best  seems  to  depend  on  local  conditions.  The  most 
important  public  methods  are  bacterial  action,  filtration  and  the 
use  of  chemical  agents. 

Bacterial  Action. — This  method  is  used  largely  in  England  and 
is  commonly  spoken  of  as  the  English  Filtering  System.     It  con- 


Fig   2  —Section  of  an  English  Filter  Bed.     (Courtesy  of  John  Wiley  &  Sons.) 

sists  of  a  filtration  through  sand-beds  which  are  filled  with  putre- 
factive bacteria.  Water  to  be  filtered  is  usually  run  into  a  sedi- 
mentation basin  first,  in  order  to  allow  suspended  matter  to 
settle  (Fig.  i).  This  will  prevent  a  too  rapid  clogging  of  the 
filtering  beds  if  the  water  is  materially  turbid.  After  sedimen- 
tation has  taken  place,  the  water  is  delivered  into  the  top  of  the 


FOOD   INDUSTRIES 


26  FOOD   INDUSTRIES 

beds  which  are  built  of  stone  or  concrete  and  have  drainage  pipes 
at  the  bottom,  to  discharge  the  filtered  water  into  wells.  In  the 
beds  are  placed  from  the  bottom  upward  layers  of  coarse  gravel, 
fine  gravel,  coarse  sand  and  fine  sand  (Fig.  2).  The  water 
percolates  through  the  layers  of  sand  and  gravel  to  the  drainage 
pipes  which  carry  it  away  to  the  reservoir.  Soon  a  slimy  growth 
containing  bacteria  occurs  on  top  of  the  filter  beds ;  these  bacteria 
are  the  true  purifying  agents.  For  a  long  period  after  this 
system  was  put  in  operationt  the  purification  was  supposed  to  be 
entirely  mechanical,  then  it  was  thought  to  be  due  to  oxidation. 
It  was  discovered  eventually  that  the  filter  beds  failed  to  work 
thoroughly  until  the  layer  of  slime  had  formed,  and  after  much 
experimentation  the  purification  was  traced  to  bacterial  action. 
The  slimy  mass  acts  as  a  mechanical  agent,  and  through  its  bac- 
teria causes  the  oxidation  of  organic  matter  and  destruction  of 
pathogenic  bacteria.  When  the  sediment  layer  becomes  so  dense 
that  the  required  amount  of  water  fails  to  pass  through,  it 
becomes  necessary  to  clean  the  bed  by  the  removal  of  the  top 
layer  (Fig.  3).  The  scraped-off  sand  can  be  washed  by  a  machine 
and  stored  for  future  use.  Several  days  are  required  for  the 
formation  of  a  new  sediment  layer  before  the  filter  bed  once 
more  becomes  effective. 

Filtration. — A  system  much  in  use  called  "The  American  Filter 
System"  depends  on  the  use  of  alum  and  filtration  through  sand. 
As  in  the  English  System  the  water  to  be  filtered  is  first  run  into 
a  sedimentation  basin,  after  which  potash  alum  or  aluminium 
sulphate  is  added,  i/io  to  I  grain  per  gallon.  The  water  is  then 
admitted  to  a  filter  which  is.  cylindrical  in  shape,  made  of  wood 
or  iron  and  is  filled  three-quarters  full  of  fine  sand  (Fig.  4). 
Alum  will  readily  ionize  in  water  forming  a  heavy  white  floccu- 
lent  precipitate  of  aluminium  hydrate,  jelly-like  in  appearance. 
K2A12(S04)4  +  3H20  —  A12(OH)6  +  K2SO4  +  3H,SO4. 

The  precipitate  collects  on  the  top  of  the  sand  as  the  water 
filters  through.  The  action  of  this  mass  closely  resembles  the 
clarifying  of  coffee  with  egg  albumin.  It  entangles  all  suspended 
matter  which  may  be  purely  inorganic  or  living  organisms  and 


FOOD   INDUSTRIES 


deposits  them  on  the  surface  of  the  sand.  The  jelly-like  layer 
then  acts  mechanically  much  as  the  bacterial  layer  of  the  English 
filter-beds. 

Use  of  Chemical  Agents. — Chemical  treatment  has  been  long 
used  as  a  means  of  purifying  water  and  has  been  found  very 
efficient  in  periods  of  epidemics.  Permanganate  of  potassium 
has  been  used  in  India  during  cholera  epidemics.  This  acts  as  an 


Fig.  4. — View  of  the  Interior  of  the  East  Albany,  N.  Y.,  Filter-plant. 
(Courtesy  of  John  Wiley  &  Sons.) 

oxidizer  of  the  organic  matter  in  water  and  then  attacks  the 
bacteria,  Sodium  hypochlorite,  chlorine  and  bromine  are  also 
effective  in  destroying  micro-organisms.  Perhaps  alum  is  the 
agent  most  commonly  employed  for  purifying  water.  It  was 
first  used  in  Egypt  during  the  time  of  Napoleon  to  clarify  the 
muddy  water  used  by  his  army.  As  it  has  been  previously 
described,  alum  will  form  a  precipitate  carrying  down  all  sus- 
pended matter  and  will  greatly  improve  the  appearance  of  water. 


28  FOOD    INDUSTRIES 

This  method  of  purification  is  used  quite  extensively  in  public 
baths.  For  drinking  purposes  it  should  only  be  used  in  small 
amounts.  Where  alum  has  been  used  to  throw  down  coagulated 
matter,  it  increases  the  hardness  of  a  naturally  hard  water.  In 
order  to  overcome  this  hardness,  sodium  carbonate  is  added  in 
amount  calculated  to  precipitate  all  as  carbonate  of  lime. 

Household  Methods. — Where  public  methods  cannot  be  depended 
upon  or  in  times  of  special  contamination,  it  is  often  necessary 
for  the  householder  to  purify  his  water  supply.  The  most 
common  methods  are  boiling  and  the  use  of  domestic  filters. 

Boiling. — Boiling  is  the  oldest  and  simplest  way  of  purifying 
water.  It  has  been  used  from  the  earliest  times  and  is  still  one 
of  the  most  effective  methods  that  we  have.  As  the  chief  danger 
of  a  polluted  water  comes  from  the  typhoid  bacillus,  whose 
thermal  death  point  is  below  the  boiling  point  of  water,  prolonged 
boiling  is  not  necessary.  Boiled  water  is  not  palatable  as  the  air 
has  been  driven  out.  It  is  well  to  cool  and  pass  it  from  one 
vessel  to  another  or  to  agitate  it  in  contact  with  the  air  to  restore 
the  original  taste. 

Use  of  Domestic  Filters. — Most  of  the  many  varieties  of  house 
filters  remove  only  dirt,  iron  rust  and  other  coarse  particles  in 
suspension.  They  are  usually  small  in  size  and  contain  a  com- 
paratively small  amount  of  sand  or  charcoal.  While  sand  is 
effective  on  a  large  scale  and  charcoal  is  a  well-known  deodorizer 
and  clarifier,  the  amount  is  not  enough  to  affect  a  large  quantity 
of  water  run  through  them,  with  the  pressure  of  the  ordinary 
city  supply.  In  a  very  short  time  these  filters  become  impreg- 
nated with  bacterial  life,  the  growth  and  development  of  which 
soon  make  them  a  dangerous  medium  through  which  to  pass 
water.  Effective  filters,  however,  can  be  bought,  but  at  a  much 
higher  price  than  the  ordinary  house  filter.  The  Berkefeld 
(Fig.  5),  Pasteur-Chamberland  and  Aqua  Pura  are  filters  of  this 
type.  The  filtering  medium  in  the  first  two  is  unglazed,  well- 
baked  porcelain,  and  in  the  latter,  sandstone.  Both  of  these 
media  are  capable  of  holding  back  micro-organisms  as  well  as 
suspended  matter.  Great  care  must  be  given  these  filters  to  have 


FOOD    INDUSTRIES 


29 


them  work  effectively.  Bacteria  soon  cover  the  filtering  surface 
and  must  be  cleaned  off  by  scraping  or  scrubbing.  Most  filters 
of  this  type  also  require  sterilization  by  baking,  boiling  or  sub- 


Fig.  5.— The  Berkefeld  Filter. 

jecting  them  to  live  steam.    Unless  the  housekeeper  is  willing  to 

give  the  filter  proper  care  it  is  far  safer  to  simply  boil  the  water. 

Manufacturers'   Method. — Boiling   on   a   large   scale   has   been 


Fig.  6.— Distillation  Apparatus.     (Courtesy  of  Carl  H.  Schultz  Co.) 


30  FOOD   INDUSTRIES 

found  so  troublesome,  that  most  manufacturers  who  must  purifv 
water  before  using  it  prefer  the  method  of  distillation  (Fig.  6). 
Here  water  is  raised  to  the  boiling  point,  passes  off  as  steam  to 
another  receptacle  where  it  is  condensed.  This  produces  a  sterile 
water  as  bacteria  do  not  pass  over  in  the  distillate.  It,  however, 
is  tasteless  and  needs  aeration. 

Self -purification. — In  the  examination  of  surface  waters,  it  has 
frequently  been  found  that  water  taken  from  a  river  at  a  given 
point  contains  a  certain  amount  of  impurities;  at  another  point 
farther  down  there  is  considerably  less,  while  at  a  still  greater 
distance  it  is  practically  pure.  This  is  supposed  to  be  due  to  the 
fact  that  water  can  in  time  bring  about  its  own  purification.  It 
is  accounted  for  in  several  ways  :  first,  the  water  becomes  diluted ; 
second,  changes  take  place  due  to  oxidation  and  bacterial  action ; 
third,  sedimentation ;  fourth,  purifying  influence  of  algae  and 
other  low  forms  of  vegetable  life. 

Could  these  agents  always  be  relied  upon  there  would  be  no 
need  of  constructing  and  maintaining  expensive  filtration  plants. 
Undoubtedly  they  produce  great  results  in  many  cases,  but  at 
other  times  the  purification  is  only  partial  while  at  times  it  is  of 
no  special  value.  There  is  great  danger,  therefore,  in  relying  on 
water  to  purify  itself.  Conditions  might  exist  or  arise  which 
would  prevent  these  agents  from  doing  their  work.  Where  self- 
purification  is  used,  every  precaution  should  be  taken  by  the 
local  authorities  to  guard  the  entire  water-shed  from  all  possible 
contamination. 

Judging  a  Water  Supply. — In  regard  to  a  drinking  water  the 
world  at  large  still  retains  the  primitive  idea,  that  purity  in 
appearance  alone  is  necessary  in  judging  a  safe  water.  Expert 
examination  has  shown  that  appearance  alone  is  of  little  value. 
A  pure  water  is  generally  bright  and  sparkling,  but  it  has  been 
found  that  some  highly  contaminated  waters  show  remarkable 
brilliancy.  On  the  other  hand  water  may  be  distinctly  muddy, 
owing  to  minute  particles  of  clay  or  turbid  from  the  effect  of 
iron,  and  still  not  be  dangerous.  Neither  can  safety  be  judged  by 
color  and  odor.  Color  may  be  due  to  traces  of  iron  or  to  leaves 


FOOD    INDUSTRIES  31 

and  other  such  color  imparting  substances.  The  presence  of  color 
does  not  indicate  that  water  is  unfit  for  domestic  use,  neither 
does  the  absence  of  color  indicate  purity,  for  many  polluted 
waters  are  colorless.  Repulsive  odors  in  water  usually  mean 
stagnation,  presence  of  dead  animals  or  other  decomposing  organic 
matter  which  makes  it  unfit  for  drinking  purposes,  but  many 
odors  may  be  present  in  water  which  are  perfectly  harmless  as 
grassy  or  peaty  odors.  The  only  safe  way  of  judging  the  purity 
of  a  water  supply  is  by  chemical  and  bacterial  tests.  The  chem- 
ical examination  usually  made  is  for  the  presence  of  organic 
matter,  and  consists  of  the  quantitative  examination  for  the  total 
solids,  free  ammonia,  albuminoid  ammonia,  nitrites,  chlorides 
and  oxygen  consuming  power.  Such  tests  to  be  reliable  should 
not  be  made  by  the  amateur,  but  by  an  expert  chemist  in  a  room 
set  apart  for  this  purpose. 

Great  care  should  be  given  in  collecting  a  sample  of  water  to 
be  sent  for  examination,  since  careless  handling  would  make  the 
analysis  worthless.  If  the  bottles  have  not  been  provided  by  the 
chemist,  a  glass  bottle  or  a  demijohn  which  has  been  thoroughly 
cleaned  and  fitted  with  a  glass  stopper  or  new  cork  can  be  used. 
Details  in  regard  to  further  directions  for  collecting  samples,  the 
significance  of  the  tests  and  analytical  methods  can  be  found  in 
"Air,  Water  and  Food"  by  Richards  and  Woodman  or  other 
standard  works  on  water  analysis. 

Ice  Supply. — The  taking  of  ice  from  polluted  waters  has  been 
a  subject  much  discussed  of  late  years.  Many  micro-organisms 
including  typhoid  are  not  killed  by  freezing,  and  it  is  claimed  by 
many  scientists  that  such  ice  is  dangerous  if  put  into  drinking 
water  for  cooling  purposes.  It  is  a  well-known  fact  that  cold 
storage  food  will  deteriorate  rapidly  when  taken  from  ice.  This 
would  not  be  true  if  bacterial  life  had  been  destroyed.  It  has 
been  discovered,  however,  that  after  prolonged  freezing  most 
germs  are  practically  harmless,  and  for  that  reason  some  scien- 
tists claim  that  ice  is  safe  to  use  even  if  taken  from  a  con- 
taminated water.  If  there  is  any  doubt  of  the  ice  supply,  it  is 


32  FOOD    INDUSTRIES 

far  safer  to  chill  drinking  water  by  placing  it  in  bottles  on  ice, 
rather  than  by  putting  the  ice  directly  into  the  water. 

MINERAL  WATERS. 

The  term  mineral   water  is   usually   applied   to   spring   water 
which  contains  a  larger  volume  of  gases  dissolved  in  it,  or  more 
solid  matter  in  solution  than  ordinary  drinking  water.     It  may, 
therefore,  exert  a  different  effect  on  the  human  body. 
Classification. — Acidulous. 
Alkaline. 
Bitter. 
Sulphur. 
Chalybeate. 
Acid. 
Alum. 
Borax. 
Saline. 
Lithia. 
These  mineral  waters  may  be  either  natural  or  artificial. 

Natural  Mineral  Springs. — Mineral  springs  have  been  found  in 
many  countries  of  both  the  Old  and  New  World,  and  from  the 
early  ages  have  attracted  much  attention.  They  often  present 
remarkable  appearances  when  relieved  from  subterranean  pres- 
sure by  losing  their  gases  with  great  rapidity.  This  often  causes 
them  to  be  thrown  upward  to  a  height  of  20-40  feet  accompanied 
by  a  hissing  or  rumbling  noise.  Some  waters  are  icy  cold  while 
others  are  at  a  boiling  heat.  These  and  other  phenomena  led  to 
many  superstitious  beliefs  in  the  early  ages,  and  these  waters 
were  supposed  to  possess  supernatural  properties.  There  is, 
however,  nothing  unnatural  about  their  origin.  Subsoil  water 
containing  a  considerable  amount  of  carbon  dioxide  may  sink  to 
great  depths,  and  may  be  subjected  to  great  pressure  or  even 
heat.  Should  such  water  find  an  outlet  it  would  tend  to  escape 
with  considerable  force.  Much  of  the  dissolved  matter  undoubt- 
edly is  obtained  from  rocky  soil  through  which  the  water  has 
percolated.  The  solvent  action  of  water,  greatly  increased  by 


FOOD  INDUSTRIES  33 

the  presence  of  carbon  dioxide  and  sometimes  heat,  may  take 
from  one  type  of  rock  certain  acids  which  later  react  with  basic 
elements  dissolved  from  another  rock,  thus  producing  salts.  Salts 
of  lime,  magnesium  and  iron  are  quite  frequently  found  in  these 
waters. 

Occurrence. — Mineral  springs  have  been  found  to  occur  most 
frequently  in  volcanic  districts  where  there  is  much  carbon 
dioxide  and  many  mineral  compounds.  They  also  occur  in  many 
other  parts  of  the  world  and  there  are  but  few  countries  where 
they  have  not  been  found.  France,  Germany,  Italy,  Spain, 
Greece,  Asia  Minor,  United  States,  and  Canada  are  rich  in  min- 
eral springs,  while  they  can  also  be  found  in  Great  Britain, 
Sweden,  Norway  and  in  many  parts  of  Africa  and  the  Orient. 

Medicinal  Power. — Mineral  waters  have  been  used  as  medic- 
inal agents  from  very  early  periods.  The  pages  of  ancient 
authors  frequently  contain  wonderful  tales  of  their  curative 
power,  and  records  speak  of  resorts  where  the  sick  bathed  in 
healing  waters  or/  drank  of  medicinal  fountains.  These  mineral 
springs  seemed  to  have  played  an  important  part  in  the  religion 
of  some  nations,  for  the  Greeks  frequently  erected  their  temples 
near  such  places,  where  their  gods  could  be  worshiped  and  their 
sick  healed  of  whatsoever  disease  they  had.  In  the  pages  of 
Latin  writers  we  meet  often  with  allusions  to  medicinal  springs, 
and  the  splendor  of  the  buildings  erected  in  their  vicinity  in 
Italy  testify  to  the  esteem  in  which  they  were  held  by  the 
Romans.  This  faith  in  the  curative  power  has  come  down  from 
these  early  times  to  the  present  day.  How  much  they  do  really 
affect  disease  is  a  question  of  much  interest  to  the  modern  phy- 
sician. Great  difficulty  is  experienced  by  investigators  of  the 
subject  for  it  is  hard  to  eliminate  other  circumstances  which  con- 
tribute to  the  cure  of  the  patient.  A  different  climate,  possibly 
a  change  in  altitude  alone  has  a  remarkable  effect  in  many  dis- 
eases. Different  diet,  complete  rest,  change  in  hours  of  going  to 
bed  and  getting  up,  new  and  possibly  cheerful  society,  relief  from 
the  harassing  cares  of  business  or  demands  of  social  life  are 
obtained.  Patients  after  a  short  period  at  these  springs  return 


34  FOOD   INDUSTRIES 

to  their  homes  much  improved,  many  times  entirely  due  to  rest, 
recreation,  more  open-air  exercise,  regular  habits,  etc.  It  is 
hardly  fair,  however,  to  state  that  the  waters  have  had  no  part 

CARBONIC  ACID  CAS 
GENERATOR. 


Fig.  7. — Carbon  Dioxide  Generator.  By  allowing  sulphuric  acid  to  flow  drop  by  drop 
from  the  upper  container  into  the  lower  tank  which  is  filled  with  a  solution  of 
bicarbonate  of  soda,  carbon  dioxide  gas  is  obtained.  (Courtesy  of  Carl  H.  Schultz 
Co.) 

in  the  benefits  obtained.  The  feeling  against  these  mineral 
springs  or  spas  as  they  are  frequently  called  has  come  largely 
from  the  quackery  surrounding  the  resorts.  The  superstition  of 


FOOD    INDUSTRIES  35 

past  ages  gave  to  them  the  power  of  curing  all  diseases.  This 
same  "cure-all"  style  of  advertisement  is  still  largely  used  by 
proprietors  of  springs  and  local  physicians  in  the  hope  of  attract- 
ing large  crowds,  and  has  done  much  to  bring  odium  on  the  spas 
and  to  disgust  the  modern  scientist.  Before  taking  these  waters 
care  should  be  given  that  the  water  is  effective  for  the  specific 
disease,  and  that  sanitary  conditions  surrounding  the  springs  have 
been  carefully  guarded.  There  is  no  reason  to  believe  that  min- 
eral water  will  not  become  as  highly  contaminated  as  ordinary 
drinking  water  if  exposed  to  sewage.  It  has  long  been  a  custom 
also  to  bottle  and  sell  mineral  waters,  and  should  they  be  con- 
taminated, disease  can  readily  be  carried  to  all  parts  of  the 
country. 

Artificial  Mineral  Waters. — In  the  latter  part  of  the  eighteenth 
century,  Joseph  Priestly  suggested  that  an  artificial  aerated  water 
could  be  made  by  charging  water  with  carbon  dioxide.     The  gas 
was  obtained  by  the  action  of  oil  of  vitriol  on  chalk. 
H2S04  +  CaC03  -~  C02  +  H.2O  +  CaSO4. 

This  carbonated  water  is  still  largely  used,  but  most  manufac- 
turers at  the  present  time  prefer  to  use  bicarbonate  of  soda  as  a 
means  of  generating  the  gas,  as  the  soda  compound  being  soluble 
is  less  troublesome  (Fig.  7). 

H2SO,  +  2NaHCO3  •—  2CO2.  +  2H2O  +  Na2SO4. 

From  this  simple  suggestion  of  Priestly  has  grown  an  industry 
for  making  not  only  carbonated  water,  but  mineral  waters  closely 
resembling  the  natural  mineral  springs.  By  careful  analysis  of 
the  spas,  chemists  have  been  able  to  combine  mineral  salts  in  the 
same  proportions,  thus  giving  an  artificial  water  claimed  by 
many  to  be  as  beneficial  as  the  natural  water.  Care  should  be 
given,  however,  in  the  use  of  these  waters  that  the  firm  placing 
them  on  the  market  is  thoroughly  reliable. 


CHAPTER  III. 


THE  KING  OF  CEREALS.     OLD  MILLING  PROCESSES. 

Taking  the  civilized  world  as  a  whole,  both  in  the  quantity 
produced  and  in  its  value  as  a  human  food,  wheat  has  won  the 
name  of  the  world's  King  of  Cereals.  It  is  the  cereal  best 
adapted  for  bread-making  and  appears  to  meet  the  needs  of 
civilized  life  more  than  the  other  grain  foods.  As  the  standard 
of  living  advances  in  a  nation,  wheat  has  grown  steadily  in  com- 
mercial importance. 

If  there  were  time  to  look  thoroughly  into  the  history  of  this 
cereal,  we  should  find  that  the  growth  and  development  of  wheat 
has  been  interwoven  with  the  very  life  history  of  the  human  race. 
Origin. — It  is  impossible  to  tell  how  long  it  has  been  utilized 
as  a  food  by  mankind,  for  archaeologists  claim  that  its  record 
began  in  prehistoric  times.  The  most  ancient  languages  mention 
it  and  the  fact  that  it  has  been  found  in  the  earliest  habitations 
of  man  is  a  proof  of  its  antiquity.  Specimens  have  been  dis- 
covered in  the  Swiss  lake  dwellings  and  among  the  remains  of 
Egyptian  civilization.  The  Chinese  claim  that  it  was  grown  in 
their  Empire  over  3,000  years  before  the  Christian  Era  and  the 
Bible  mentions  its  use  as  early  as  the  Book  of  Genesis.  If  these 
accounts  be  true,  wheat  must  have  kept  its  place  in  man's  diet 
for  nearly  6,000  years.  Such  a  record  of  long,  faithful  service 
could  not  be  unless  the  grain  of  wheat  had  locked  up  within  its 
kernel  the  elements  which  are  most  needed  to  maintain  heat, 
and  replace  the  energy  and  tissue  which  are  constantly  being 
worn  away  during  life's  processes.  The  savage  in  his  hunger 
seemed  to  have  instinctively  turned  to  it  as  a  food,  and  the  wis- 
dom of  his  choice  can  readily  be  seen  by  a  study  of  its  composi- 
tion as  given  by  Dr.  H.  W.  Wiley,  formerly  of  the  United  States 
Department  of  Agriculture. 

Water 10.60 

Protein    12.25 

Fat   1.75 

Fiber    2.40 

Starch,  etc 71.25 

Ash 1.75 


FOOD    INDUSTRIES  37 

Geographical  Distribution. — The  raising  of  wheat  has  so  long 
been  a  practice  with  man  that  the  geographical  origin  is  unknown. 
Egyptians  attribute  its  discovery  to  Isis  and  the  Chinese  claim 
to  have  received  the  seed  as  a  direct  gift  from  Heaven.  It  was 
at  one  time  the  custom  for  the  Chinese  Emperor  to  drive  the 
plow  in  order  to  do  homage  to  the  dignity  of  agriculture.  The 
belief  that  it  originated  in  the  Valley  of  the  Euphrates  and  Tigris 
is  more  widely  accepted  than  any  other  theory.  Early  it  spread 
into  Phoenicia  and  Egypt,  finding  a  most  suitable  lodging  place 
along  the  shore  of  the  Mediterranean.  The  climate  there  was 
suited  to  its  cultivation,  dry  and  hot  during  the  summer  months. 
Italians  as  far  back  as  the  early  Roman  days  obtained  part  of 
their  wheat  supply  from  the  north  of  Africa,  for  that  war-like 
nation  was  unable  to  produce  enough  wheat  for  its  own  con- 
sumption. Many  of  their  warfares  were  for  the  purpose  of 
capturing  the  harvest  from  their  more  successful  wheat  growing 
neighbors. 

The  migration  of  wheat  from  those  early  days  was  closely 
connected  with  the  migration  of  the  human  race:  Gradually 
spreading  throughout  Europe,  it  finally  reached  Germany, 
France  and  Great  Britain,  although  this  latter  country  has  never 
been  able  to  grow  enough  wheat  to  supply  its  population.  Great 
Britain  still  obtains  much  of  its  wheat  from  countries  where  con- 
ditions are  more  favorable  for  the  growth  of  this  cereal.  Extend- 
ing into  Russia,  wheat  once  more  found  a  suitable  soil  and 
climate  which  in  time  produced  so  large  a  supply,  that  Russia 
became  known  as  "The  Granary  of  Europe."  That  title  she 
continued  to  keep  until  the  famine  of  1891-92  swept  the  country 
with  a  terrible  scourge  and  from  which  she  has  never  fully  recov- 
ered. The  failure  of  the  crops  during  those  years  was  caused 
not  only  by  bad  weather,  but  by  the  continued  use  of  crude  agri- 
cultural methods  which  in  time  thoroughly  impoverished  the  soil. 
Should  she  use  more  up-to-date  methods  in  regard  to  fertilizing, 
she  might  again  regain  that  title,  but  the  yield  per  acre  at  present 
is  very  small.  The  peasantry  still  cling  to  old  methods  slightly 
in  advance  of  the  Middle  Ages.  In  Russia,  there  are  still 


38  FOOD   INDUSTRIES 

immense  undeveloped  areas  that  would  make  ideal  wheat  fields 
and  much  is  being  looked  for  in  the  Siberian  wheat-growing 
area.  It  is  difficult  to  predict,  however,  what  part  the  Russian 
Empire  will  play  in  the  wheat  market  of  the  future.  The  possi- 
bilities are  very  great,  but  many  changes  must  first  be  brought 
about  in  the  political  and  social  condition  of  the  people,  for 
Russia  is  still  sadly  lacking  in  the  institutions  that  are  necessary 
to  bring  about  progress  and  prosperity.  Even  with  these  great 
drawbacks  Russia  is  still  one  of  the  greatest  wheat  producing 
countries  of  the  world,  largely  due  to  the  Siberian  wheat  fields. 

When  civilization  moved  westward,  it  -was  found  that  wheat 
could  be  grown  in  the  New  World  for  that  cereal  readily  adapts 
itself  to  new  environments.  Starting  along  the  Atlantic  coast, 
it  pushed  farther  and  farther  westward  with  the  march  of  civili- 
zation, flourishing  wheat  fields  shortly  replacing  the  primeval 
forest.  When  the  wheat  line  had  reached  Ohio  it  was  thought 
by  many  European  nations  to  have  reached  its  limit  on  American 
soil.  Warning  was  given  to  the  Ohio  farmer  to  care  for  the 
soil,  for  with  the  rapid  growth  of  the  United  States  it  was  feared 
that  the  population  would  soon  outrun  its  wheat  production. 
But  the  wheat  line  was  not  to  stop;  in  the  opening  up  of  the 
northwest,  this  cereal  was  again  to  find  favorable  conditions  for 
its  growth.  With  fertile  soil,  intellectual  farming,  American 
enterprise  and  capital,  the  United  States  advanced  to  one  of  the 
leading  wheat  producing  nations  of  the  world. 

Still  farther  north  the  wheat  line  was  to  travel,  for  it  has  been 
found  in  recent  years  that  thousands  of  acres  of  land  in  Canada, 
which  were  considered  waste  land,  can  be  utilized  for  wheat 
growing.  This  area  is  nearly  three  times  as  great  as  that  used 
for  wheat  in  the  United  States  and  the  yield  per  acre  is  larger. 
As  yet  only  about  5  per  cent,  of  the  land  is  under  cultivation.  In 
Canada  the  United  States  has  found  a  powerful  rival.  The 
virgin  soil  is  capable  of  producing  enormous  crops  of  superb 
spring  wheat,  much  needed  to  blend  with  softer  varieties,  and 
the  men  behind  the  plow  in  this  new  wheat-producing  country 
both  read  and  think. 


FOOD    INDUSTRIES  39 

It  would  seem  that  with  the  development  of  the  northwest 
area  that  wheat  had  at  last  reached  its  limit  of  cultivation  on 
American  soil,  but  agriculturalists  prophesy  that  the  line  of 
march  will  next  turn  eastward,  and  that  much  land  now  lying 
idle  in  the  eastern  and  southern  sections  will  in  time  be  utilized 
for  the  growing  of  wheat.  With  the  development  of  drought 
resistant  varieties,  it  is  also  hoped  that  more  of  the  semi-arid 
land  of  the  west  can  be  used. 

Of  the  South  American  countries,  Argentine  Republic  has 
taken  the  first  place  as  a  producer  and  exporter  of  wheat.  Here 
are  found  great  natural  advantages,  extensive  prairies  very  sim- 
ilar to  those  of  Minnesota  and  the  Dakotas,  and  a  moderate 
climate  which  enables  the  farmer  to  work  the  land  almost  any 
time  of  the  year.  Cheap  land,  cheap  labor  and  its  nearness  to 
the  sea  are  also  important  factors.  As  in  Russia,  however,  agri- 
cultural methods  are  still  very  crude.  Land  is  not  well  cared 
for  and  the  crops  are  not  properly  stored.  This  latter  deficiency 
sometimes  affects  wheat  to  be  used  for  milling.  With  improved 
conditions,  Argentina  promises  to  be  an  important  wheat  pro- 
ducer. At  the  present  time  more  wheat  is  being  raised  than  is 
necessary  for  home  consumption,  and  large  quantities  are  being 
shipped  to  Europe. 

While  Russia,  United  States,  Canada  and  Argentina  have  been 
the  most  important  wheat-producing  countries,  this  cereal  can  be 
cultivated  in  a  variety  of  climates.  Regions  having  cold  winters 
produce  most  of  the  world's  wheat,  but  marked  exceptions  are 
found  in  Egypt  and  India.  While  Egyptian  wheat  is  of  little 
commercial  importance  to-day,  in  the  age  of  the  Pharaohs  and 
during  the  Roman  civilization,  Egypt  was  the  wheat  center  of 
the  world. 

Cultivation. — Wheat  has  always  been  a  cereal  that  has  needed 
the  care  of  mankind;  wild  varieties  are  practically  unknown. 
Little  is  told  us  in  history  of  how  the  farmer  of  antiquity  tilled, 
sowed  and  harvested  his  crop  and  it  was  not  until  the  days  of 
the  Roman  Censor,  Cato  (234-149  B.  C.),  that  any  written  work 
can  be  found  on  the  subject  of  agriculture.  The  tillers  of  the 
4 


4O  FOOD    INDUSTRIES 

soil  have  always  been  marked  by  their  independence,  and  it  was 
not  until  modern  times  that  we  found  co-operation  among  this 
class  of  workers.  The  early  farmer  worked  many  times  in  a 
more  or  less  isolated  position,  independent  and  non-progressive, 
teaching  his  son  and  grandson  to  follow  in  his  footsteps.  For 
information  as  to  the  time  of  sowing,  he  had  only  the  deities  and 
medicine-men  to  consult.  For  centuries  the  farmer  was  left  to 
work  out  his  own  salvation,  but  with  the  advance  of  civilization 
very  gradually  there  arose  the  botanist,  the  physicist  and  chemist, 
the  agriculturist  and  the  bacteriologist  to  assist  him  in  his  work. 
So  important  is  the  work  of  the  scientist  in  modern  times  that  a 
single  government  has  been  known  to  spend  many  millions  of 
dollars  in  the  solution  of  a  problem  of  great  importance.  Shortly 
after  the  colonists  had  established  their  independence,  the  sug- 
gestion was  made  to  establish  a  national  board  of  agriculture, 
but  it  was  not  until  the  days  of  Lincoln  that  the  National  Depart- 
ment of  Agriculture  was  established.  The  experimentation  car- 
ried on  by  Liebig  and  other  scientists  of  his  time  led  the  way  to 
the  foundation  of  experiment  stations,  and  in  time  to  agricul- 
tural colleges  both  in  Europe  and  America.  Farmers'  institutes 
and  societies  followed  which  have  now  grown  to  be  of  national 
importance. 

Hand  in  hand  with  the  progress  of  agricultural  methods  is 
found  the  progress  in  motor  power.  For  centuries,  undoubtedly 
only  the  muscular  energy  of  man  was  used,  and  hand  labor  is 
still  employed  to  a  large  extent  in  India,  China,  Japan,  Egypt, 
Mexico  and  among  many  of  the  Eastern  and  South  American 
nations.  Animal  power  was  the  first  that  relieved  man  from  the 
drudgeries  of  agricultural  life,  the  oxen  and  the  horse  being 
almost  universally  employed.  This  power  is  still  largely  used, 
although  as  early  as  1832  steam  power  was  introduced  into  Eng- 
land, and  is  now  used  to  a  great  extent  in  the  Western  United 
States  and  in  parts  of  Germany  and  Hungary.  Much  experi- 
menting is -being  done  along  the  lines  of  electricity.  As  in  motor 
power,  so  in  implements  can  the  progress  of  the  world  be  seen 
by  a  comparison  of  the  early  plow  as  seen  on  Egyptian  monu- 


FOOD   INDUSTRIES  41 

ments  with  the  modern  combined  harvester  of  the  great  north- 
west. 

Structure  of  the  Wheat  Grain. — (Figs.  8  and  9.)  I.  Husk.— 
The  husk  is  the  outer  layer  and  serves  as  a  covering,  thus  protect- 
ing the  grain  from  the  attack  of  its  enemies  in  much  the  same  way 
as  the  shell  does  the  nut.  It  is  composed  largely  of  cellulose,  a 
woody  fibrous  material  not  available  as  human  food. 

II.  Bran  coats  lie  directly  under  the  outer  covering  and  are 


Fig.  8.— longitudinal  Section  Through  a  Grain  of  Wheat. 

composed  of  several  distinct  layers  mostly  cellulose  impregnated 
with  mineral  matter.  Here  too  are  found  cells  full  of  pigment 
which  give  to  the  bran  its  characteristic  color.  Directly  under- 
neath the  bran  coats  is  found  a  single  layer  of  large  cells  full  of 
granular  material  of  a  protein  nature.  This  coating  completely 
encloses  the  endosperm  and  germ  and  is  usually  spoken  of  as  the 
layer  of  aleurone  cells  or  the  cerealine  layer. 

III.  The  endosperm  is  the  largest  and  most  important  part  of 


42  FOOD   INDUSTRIES 

the  kernel;  it  is  the  food  part  of  the  grain,  the  portion  utilized 
in  the  making  of  ordinary  flour.  It  contains  cellulose  in  the  cell 
walls,  a  small  amount  of  mineral  matter,  sugar  and  practically 
all  of  the  starch  and  protein  available  as  food.  Nature  designed 
it  to  serve  as  food  for  the  young  plant  during  the  early  stages 
of  growth. 


Fig.  q.— Section  Through  Part  of  a  Grain  of  Wheat. 
a — Cellular  Structure,     b — Starch  Granules,    c — Protein. 

IV.  The  germ  is  the  part  from  which  the  plant  is  to  be  repro- 
duced. It  is  more  complex  in  its  composition,  containing  cellu- 
lose and  soluble  carbohydrates,  a  large  proportion  of  nitrogenous 
matter  and  is  rich  in  oils  and  mineral  matter. 

Value  of  Wheat. — Its  wide  adaptation  to  different  climates  and 
soils,  the  ease  of  cultivation,  a  quick  and  abundant  harvest,  great 
number  of  varieties  and  the  intrinsic  food  value  of  the  kernel 
would  be  sufficient  to  make  wheat  the  leading  food  grain.  There 
is  still  another  reason,  however,  which  gives  it  the  rank  of 
king  among  cereals.  This  lies  in  the  fact  that  it  can  be  so 


FOOD    INDUSTRIES  43 

readily  utilized  in  the  making  of  bread.  This  quality  wheat 
shares  only  with  rye  and  both  owe  their  bread  producing  power 
to  the  nitrogenous  constituents  of  the  endosperm. 

Osborne  and  Voorhies  in  their  investigation  of  the  protein 
content  of  wheat  discovered  five  distinct  proteins,  the  most 
important  of  which  were  gliadin  and  glutenin,  both  occurring  in 
the  endosperm  in  about  the  same  amount,  4.25  per  cent,  of  the 
entire  grain.  In  the  presence  of  water  these  proteins  unite  to 
form  gluten.  To  the  peculiar  properties  of  this  gluten,  wheat 
bread  owes  its  lightness  and  digestibility,  thus  giving  it  first  place 
among  the  civilized  nations  of  the  world.  The  other  cereals  con- 
tain similar  proteins,  but  not  in  the  right  proportion  to  form 
gluten.  With  rye  flour,  gluten  can  be  formed,  but  it  does  not 
make  as  light  or  as  acceptable  a  loaf. 

Varieties. — Migrating  as  it  has  for  many  centuries,  meeting 
different  conditions  of  climate,  soil  and  methods  of  cultivation, 
wheat  is  now  grown  in  a  vast  number  of  varieties.  The  United 
States  Department  of  Agriculture  after  long  experimentation 
reduced  the  number  to  245  leading  varieties.  For  the  sake  of 
convenience  wheat  can  be  divided  into  two  large  classes,  winter 
wheat  and  spring  wheat. 

Winter  Wheat. — For  the  varieties  of  winter  wheat,  seeds  are 
planted  in  the  fall.  Enduring  the  cold  and  dampness  of  the 
winter,  a  maximum  of  starch  and  a  minimum  of  protein  are 
developed  in  the  endosperm.  Flour  made  from  this  wheat  is 
soft  and  does  not  give  enough  gluten  to  make  as  desirable  a 
loaf  of  bread  as  spring  varieties,  yet  it  was  the  flour  used  among 
the  so-called  civilized  nations  of  Europe  until  the  time  of  Liebig. 
He  was  the  first  to  suggest  that  the  right  kind  of  flour  was  not 
being  used  for  bread-making.  Either  the  process  of  milling 
must  be  changed  or  a  new  wheat  must  be  grown.  His  experi- 
mentation was  along  the  lines  of  agriculture,  to  grow  a  variety 
higher  in  gluten- forming  proteins  and  lower  in  starch  content. 

Spring  Wheat. — Amid  much  ridicule  and  after  many  failures, 
Liebig  finally  convinced  agriculturalists  that  wheat  for  bread- 
making  should  be  grown  quickly.  The  temperature  was  most 


44  FOOD    INDUSTRIES 

important;  dry,  hot  weather  was  necessary.  Seed  if  planted  in 
the  spring  would  ripen  in  the  early  summer  or  fall  and  be  ready 
for  harvesting  in  August  or  September.  This  opened  a  new  era 
in  the  cultivation  of  wheat.  Soon  a  hard  spring  wheat  was 
being  grown  that  in  time  was  utilized  largely  for  the  making  of 
bread.  An  extended  study  of  its  production  brought  about  many 
reforms  along  agricultural  lines  which  were  also  felt  by  the 
growers  of  winter  wheat.  These  new  ideas  have  enabled  farmers 
to  grow  many  varieties  of  winter  wheat  higher  in  their  protein 
constituents  than  the  first  spring  wheat  grown.  With  the  devel- 
opment of  hard  spring  varieties,  new  milling  processes  were 
found  necessary,  the  development  of  which  was  to  place  the 
miller  among  the  world's  manufacturers. 

OLD  MILLING  PROCESSES. 

The  history  of  wheat  would  be  far  from  complete  without  a 
study  of  milling  processes,  for  the  story  of  wheat  must  ever  be 
intimately  connected  with  the  history  of  the  production  of  flour. 
Here  again  we  find  wonderful  progress  from  the  rude  processes 
of  ancient  civilizations  to  the  modern  roller  mills,  where  can  be 
seen  the  greatest  mechanical  perfection  and  whose  capacity  is  so 
great,  that  they  can  produce  in  a  single  day  enough  flour  to  feed 
a  small  city  for  an  entire  year. 

It  has  been  suggested  that  wheat  was  first  eaten  raw,  for  when 
driven  by  the  pangs  of  hunger  primitive  man  plucked  the  wheat 
grain  from  the  stalk,  using  his  teeth  as  mill-stones,  and  that  it 
was  this  grinding  motion  which  first  gave  him  the  idea  of  invent- 
ing some  rude  instrument  which  would  break  up  the  hard  berry 
for  him.  Whether  this  idea,  be  true  or  not,  we  find  that  various 
forms  of  apparatus  were  early  invented  to  make  the  grinding 
process  easier  and  more  effective.  All  primitive  nations  reduced 
grain  to  a  meal  by  means  of  a  hand-stone. 

Hand-stones. — The  form  of  these  stones  was  varied,  but  they 
all  consisted  of  two  stones,  one  of  which  held  the  grain  while  the 
other  was  used  for  pounding.  Fig.  10.  The  first  real  grinding 
came  into  use  when  the  lower  stone  was  given  a  concave  surface 


FOOD  INDUSTRIES  45 

and  the  grain  being  placed  within  the  hollow  was  rubbed  back 
and  forth  by  means  of  a  stone-crusher.  These  primitive  mills 
were  always  operated  by  women  and  were  the  only  mills  used 
for  some  four  thousand  years.  They  must  have  been  used  by 
the  aboriginals  of  all  countries,  for  large  numbers  of  them  have 
been  found  showing  their  use  among  the  prehistoric  Swiss  lake 
dwellers,  the  Babylonians,  the  natives  of  Nineveh,  Assyria  and 
Egypt'  and  again  in  many  parts  of  the  New  World.  So  far  as 
their  structure,  detail  and  finish  are  concerned,  tablets  indicate 
that  saddle-stones  made  this  side  of  the  Atlantic  were  superior 
to  those  of  Europe  and  Africa.  Milling  was  not  a  separate  indus- 
try, but  part  of  the  work  of  each  household  in  which  the  meal 


Fig.  io.— Hand-stone. 

was  first  made  then  baked  into  cakes  or  bread.  In  some  parts 
of  the  world  this  operation  is  still  carried  on.  In  sections  of  the 
northern  part  of  Africa  women  are  the  millers,  doing  their  work 
in  saddle-stones  in  much  the  same  way  as  it  was  done  in  the 
earliest  historic  times. 

The  Mortar  and  Pestle. — In  time  the  stone-crusher  became 
elongated  into  the  pestle,  and  the  saddle-stone  was  fashioned  into 
the  mortar  (Fig.  n).  This  marked  the  step  from  barbarism  into 
civilization.  In  the  mortar  period  the  Greeks  substituted  men 
as  flour-makers.  These  men  were  called  pounders  and  in  the 
decline  of  Grecian  supremacy,  a  band  of  them  were  led  captives 
into  Rome.  As  prisoners  of  war,  these  craftsmen  were  set  to 


46  FOOD    INDUSTRIES 

work  at  their  occupation,  grinding  and  baking.  From  this  fol- 
lowed the  custom  of  using  slaves  as  the  millers  during  the  days 
of  the  Roman  Empire. 

Quern. — To  the  Romans,  the  ancient  world  was  indebted  for 
inventing  the  first  milling  machine  in  which  the  parts  were 
mechanically  combined.  It  was  a  simple  grinding  machine  giving 
a  circular  motion  and  was  known  as  the  quern.  It  consisted  of 
two  stones,  the  upper  one  conforming  to  the  shape  of  the  lower 
upon  which  it  revolved.  This  upper  stone  was  hollowed  out  in 


Fig.  ii.— The  Mortar  and  Pestle. 

the  center,  making  a  hole  sufficiently  large  to  receive  the  grain 
to  be  ground  and  had  on  the  side  a  handle  to  facilitate  the  turn- 
ing of  the  stone.  This  was  the  mill  in  use  at  the  dawn  of  the 
Christian  Era  and  it  still  can  be  found  in  China,  Japan,  among 
the  Arabs  and  in  some  isolated  sections  of  Europe.  It  was  the 
original  British  flour  mill  and  was  destined  in  that  country  to  be 
the  cause  of  a  long  political  strife.  In  the  early  days  of  the  use 
of  the  quern,  women  did  the  grinding,  but  gradually  this  work 
was  given  to  slaves  and  criminals.  The  first  marked  improve- 


FOOD    INDUSTRIES  47 

ment  was  the  grooving  of  the  grinding  faces  of  the  stones  and 
in  time  the  enlargement  of  the  mill. 

As  the  quern  increased  in  size  another  motor  power  was  found 
necessary.  This  for  a  long  period  in  many  countries  was  sup- 
plied by  cattle,  although  in  parts  of  northern  and  western  Europe 
the  water  mill  early  came  into  use.  With  the  enlargement  of 
the  mill  and  the  introduction  of  different  motor  power,  milling 
passed  from  the  household  to  the  hands  of  the  professional 
miller,  who  at  first  did  the  village  grinding,  then  passed  to  a 
larger  district.  In  some  countries  wind  was  used  instead  of 
water  and  we  find  crude  wind-mills  appearing  as  early  as  600 
A.  D.  The  earliest  mills  of  the  United  States  were  operated  by 
horse-power,  wind  and  water  being  later  introduced. 

Grist  Mills. — While  the  motor  power  was  being  changed,  devel- 
opments appeared  in  the  mill-stones  and  the  grist  mill  came  into 
existence.  At  the  end  of  the  eighteenth  century  this  mill,  driven 
by  either  wind  or  water,  was  doing  a  thriving  business  and  it  is 
only  a  comparatively  short  time,  since  it  had  to  give  away  to  the 
modern  roller  mill.  The  structure  at  first  was  of  few  parts  and 
the  operation  was  simple.  The  entire  wheat  went  into  the  flour ; 
there  was  no  bolting  and  no  separation  into  grades.  The  grain 
was  at  first  crudely  cleaned  by  screening,  blasts  of  air  being 
passed  over  the  wheat  to  blow  away  chaff  and  lighter  particles. 
The  wheat  was  then  passed  to  the  mill-stones  to  be  ground.  Two 
large  stones  known  as  burr-stones  were  used,  the  lower  one  of 
which  revolved.  They  were  very  heavy,  sometimes  weighing 
1,500  pounds,  and  as  a  rule  were  imported  from  France.  The 
stones  were  made  up  of  pieces  bound  together  with  bands  of 
iron.  The  inner  surface  was  cut  much  like  a  grater  and,  as  it 
wore  smooth,  the  miller  would  again  cut  its  surface  with  a  steel 
pointed  hammer  called  a  mill-pick  (Fig.  12).  When  the  two 
stones  touched  in  revolving,  it  was  spoken  of  as  "low  milling." 
The  grain  was  fed  from  above  and  the  grinding  motion  con- 
tinued until  the  kernel  was  ground  to  a  powder.  The  outer 
husks  were  torn  into  shreds  and  the  germ,  being  plastic,  rolled 
over  and  over  until  it  assumed  a  cylindrical  form.  The  main 


48 


FOOD   INDUSTRIES 


object  of  low  milling  was  to  make  the  largest  possible  amount 
of  flour  from  the  grain  at  the  first  grinding.  The  only  separation 
made  was  that  of  the  fibrous  part  which  being  lighter  could  be 
removed  by  a  process  of  winnowing.  As  some  of  the  bran  was 


Fig.  12  —Roughening  Burr-stoues. 
(Courtesy  of  the  Wash  burn-Crosby  Co.,  Manufacturers  of  Gold  Medal  Flour.) 

pulverized  it  was  impossible  to  separate  it  from  the  flour.  This 
gave  the  flour  a  dark  color  and  impaired  its  keeping  qualities. 
The  germ  also  being  rich  in  fat  in  time  became  rancid. 

During  the  nineteenth  century  marked  improvements  took  place 


FOOD  INDUSTRIES  49 

in  milling  owing  to  the  invention  of  many  mechanical  devices. 
Screens  and  bolters  came  into  use  which  led  to  a  practice  of  sift- 
ing and  regrinding.  The  elevator,  the  conveyor,  the  drill  and 
the  hopper-bag  were  invented  and  finally  the  middling  purifier. 

With  the  invention  of  the  middling  purifier,  "high  milling" 
came  into  use.  Here  the  stones  were  placed  farther  apart  and 
the  wheat  was  granulated  rather  than  ground,  sifted  and  re- 
ground.  This  gradual  reduction  being  found  advantageous,  more 
stages  were  introduced  until  a  flour  vastly  superior  in  quality 
was  being  placed  upon  the  market. 

When  hard  spring  wheat,  however,  appeared  other  improve- 
ments were  necessary.  When  our  people  visited  Hungary,  they 
were  surprised  to  find  what  progress  had  been  made  along 
mechanical  lines.  There  the  grain  was  being  crushed  by  means 
of  rollers  made  of  porcelain.  Americans  were  very  quick  to  see 
the  advantage  of  this  process  and  a  roller-mill  outfit  was  brought 
from  Hungary  to  Minneapolis.  Many  changes  in  machinery 
were  necessary  to  meet  new  conditions,,  but  from  1881  the  roller- 
mill  rapidly  increased,  and  before  the  dawn  of  the  twentieth  cen- 
tury the  long  honored  grist  mill  had  practically  disappeared.  The 
substitution  of  rolls  for  mill-stones  was  the  most  radical  advance 
ever  made  in  the  history  of  milling.  It  made  possible  the  opera- 
tion of  large  flour  mills  which  rank  among  our  great  commercial 
industries. 

Disadvantages  of  Old  Processes. — I.  They  were  very  slow.  In 
the  grist  mill  the  stones  were  very  heavy  and  could  not  be  driven 
rapidly. 

II.  The  flour  could  not  be  ground  as  fine.     If  the  stones  were 
placed  too  close  together,  there  was  danger  of  the  stone  itself 
wearing  away  and  becoming  mixed  with  the  flour. 

III.  Friction  caused  heat  which  would  affect  enzyme  action. 
Starch  would  be  changed  to  a  more  soluble  form  and  thus  make 
the  flour  more  liable  to  be  attacked  by  molds  and  bacteria. 

IV.  The  keeping  quality  was  very  poor.     Farmers   in  olden 
times  were  in  the  habit  of  carrying  grain  to  the  mill  in  sacks  and 
carrying  home  flour.     It  was  said  that  the  farmer  was  poor  or 


50 


FOOD    INDUSTRIES 


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POOD    INDUSTRIES  51 

that  he  could  not  conveniently  carry  more,  but  these  were  not 
the  true  reasons.  He  had  learned  by  bitter  experience  that  the 
flour  would  not  keep.  It  was  long  before  the  cause  for  this  was 
known.  Old-fashioned  flour  contained  the  germ  within  which  is 
most  of  the  oil  of  the  wheat  kernel.  Oil  becoming  rancid  soon 
spoiled  and  ruined  the  flour.  In  modern  milling  processes  the 
germ  is  removed. 


CHAPTER  IV. 


MODERN  MILLING  AND  MILL  PRODUCTS. 

In  visiting  a  modern  mill,  a  curious  device  invented  for  the 
safety  of  the  mill  at  once  strikes  the  eye  of  the  visitor.  This  is 
called  a  dust-collector.  The  milling  of  wheat  always  produces  a 
large  amount  of  flour  dust  which  in  case  of  ignition  is  capable 
of  causing  a  terrific  explosion.  A  disaster  of  this  kind  in  the 
Minneapolis  mills  during  1877-78  led  to  the  development  of  a 
large  rotating  diaphragm,  which  by  suction  collects  flour  dust 
from  the  various  machines  used  throughout  the  mill,  thus  keeping 
the  atmosphere  comparatively  free  from  dangerous  particles. 

To  the  novice  there  appears  to  be  innumerable  processes  in- 
volved in  the  present  day  milling  of  wheat.  From  the  time  the 
grain  is  received,  however,  until  it  is  packed  for  shipment  as 
flour,  the  miller  has  in  mind  several  fundamental  objects ;  the 
thorough  cleansing  of  the  wheat,  tempering,  separation  out  of 
the  middlings  and  the  reduction  of  the  middlings  to  flour. 

After  the  grain  is  received  and  weighed,  it  is  carried  at  once 
by  means  of  elevators  to  the  top  of  the  mill  where  it  passes 
through  a  preliminary  process  of  cleaning. 

I.  Cleansing  of  the  Wheat. — Receiving  Separators. — These 
separators  consist  of  several  large  sieves  for  separating  out 
from  wheat  such  matter  as  corn,  sticks,  stones,  lint  and  nails. 
The  sieves  are  kept  constantly  in  motion,  are  slightly  inclined 
and  have  holes  sufficiently  large  to  allow  the  wheat  kernel  to 
pass  through.  Foreign  matter  being  retained  passes  down  the 
incline  and  is  caught  in  a  receptacle. 

Storage  Bins. — From  the  receiving  separators,  wheat  passes 
by  conveyors  to  the  storage  bins  for  a  reserve  supply  in  advance 
of  mill  requirements. 

Mill  Separators. — When  required  for  milling,  wheat  is  drawn 
to  the  mill  separators.  Here  are  a  series  of  sieves  constantly 
shaking  for  removing  dust,  dirt,  foreign  seeds  such  as  oats  and 
imperfect  kernels  of  wheat.  Perforations  are  smaller  than  those 


FOOD    INDUSTRIES  53 

of  the  receiving  separators  and  hold  back  the  wheat  while  foreign 
and  imperfect  grains  pass  through. 

Scourer. — During  the  sifting  processes  the  dust  and  dirt  have 
not  been  fully  removed.  In  this  machine  wheat  grains  are 
thrown  against  perforated  iron  screens.  This  loosens  the  dirt 
while  a  strong  current  of  air  passing  through  draws  it  out.  Some 
scouring  machines  have  brushes  attached  for  brushing  and  pol- 
ishing the  grain. 

Cockle  Cylinder. — In  the  wheat  fields  there  is  a  common  weed 
known  as  the  cockle.  It  has  a  small,  round,  black  seed  which 
frequently  becomes  mixed  with  wheat  and  must  be  separated  out 
or  the  quality  of  the  flour  will  be  impaired.  As  they  follow  the 
wheat  kernel  in  the  receiving  and  mill  separators,  a  special 
device  has  been  invented  for  their  removal.  This  is  called  the 
cockle  cylinder. 

Washing  Machine. — The  washing  process  is  usually  not  con- 
sidered necessary  in  mills,  where  scourers  or  the  dry  process  of 
cleaning  as  it  is  called  has  been  used,  unless  in  case  of  special 
contamination.  Some  millers,  however,  prefer  to  wash  all  wheat, 
afterwards  carrying  it  through  a  drying  process. 

II.  Tempering. — This  operation  is  carried  on  to  make  easier 
the   separation   of   the   outer  part   of   the   wheat   kernel   and   is 
especially  necessary  with  spring  wheat.    There  are  many  methods 
of  tempering,  but  all  consist  in  a  softening  of  the  grain  by  means 
of  heat  and  moisture.     This  may  be  accomplished  by  steam  or 
water  or  by  the  application  of  both.     The  grain  comes  through 
this  process   having  a  warm,   moist   feeling  and   ready   for  the 
grinding  process. 

III.  Separation  of  the  Middlings.— Roller  Mill— The  mill  (Fig. 
13)   consists  of  two  or  three  steel  rolls  about  2  feet  long  and 
having  small  teeth  on  the  outer  surface  for  the  purpose  of  cutting 
the  berry.     They  rotate  at   different   speed.     The  grain  passes 
from  the  rolls,  ruptured  and  flattened  and  feeling  like  damp  saw- 
dust.    The  pieces  are  comparatively  large  for  the  reduction  by 
the  roller-mill  process  is  gradual. 

Scalper. — As  the  grain  passes  from  the  first  roller  or  "break" 


54 


FOOD    INDUSTRIES 


as  it  is  sometimes  called,  it  consists  of  bran  coats  and  the  interior 
of  the  wheat  which  is  known  as  the  "middlings."  A  sifting 
process  is  next  necessary  to  separate  out  as  much  of  the  bran  as 
has  been  loosened.  The  sieve  consists  of  a  series  of  screens 
usually  covered  with  wire  or  bolting  cloth  and  is  known  as  the 
scalper. 


Fig.  J3- — Roller  Mills. 
(Courtesy  of  the  Washburn-Crosby  Co.,  Manufacturers  of  Gold  Medal  Flour.) 


Second  Roller  or  Break, — The  first  separation  was  very  crude, 
for  the  bran  coats  still  carry  much  of  the  interior  with  them. 
To  separate  out  this  material,  the  bran  is  again  passed  through 
a  roller-mill,  the  principle  of  which  is  the  same  as  the  first 


FOOD    INDUSTRIES  55 

"break,"  but  the  rolls  are  set  closer  together.     This  tears  the 
bran  into  smaller  pieces  and  frees  more  of  the  interior. 

Second  Scalper. — This  finer  product  is  again  sifted  and  more 
middlings  are  separated.  The  bran  is  now  ready  for  a  third 
grinding.  The  operations  of  rolling  and  sifting  are  carried  on 
again  and  again,  four,  five,  six  or  more  times  or  until  all  the 
middlings  have  been  obtained.  The  bran  can  be  used  as  cattle 
food. 


Fig.  14. — Middlings  Purifier  for  Taking  Impurities  from  the  Crushed  Grain. 
(Courtesy  of  the  Washburn-Crosby  Co.,  Manufacturers  of  Gold  Medal  Flour.) 

IV.  Reduction  of  the  Middlings. — The  middlings  obtained  from 
the  various  rollers  and  sifters  are  mixed  and  constitute  the  part 
that  is  to  be  made  into  flour.  There  are  three  important  machines 
met  with  in  this  operation — the  purifier,  the  smooth  roller  or 
pulverizer  and  the  bolter. 
5 


50  FOOD    INDUSTRIES 

Purifier. — The  middling  purifier  (Fig.  14)  is  very  complicated 
in  its  mechanical  structure,  but  simple  in  principle.  It  consists 
of  different  mesh  sieves  about  eight  in  number.  The  middlings 
are  fed  into  the  machine  from  above,  flow  down  in  a  thin  sheet 
while  a  current  of  air  fed  from  below  passes  outward,  carrying 
off  small  particles  of  remaining  bran.  Wheat  being  heavier 
passes  down  through  the  sieves  and  is  caught  in  a  receptacle 
from  which  it  is  conveyed  to  the  smooth  roller. 


Fig.  15. — The  Modern  Sieve  or  Bolter.     (Courtesy  of  the  Hecker-Jones-Jewell  Milling  Co.) 

Smooth  Roller. — These  rolls  are  made  of  steel  and,  as  the 
name  indicates,  are  smooth.  They  are  really  pulverizers.  The 
purified  middlings  passing  under  the  smooth  roller  are  ground 
fine;  this  is  the  first  reduction  to  the  powder  form,  although  not 
all  is  reduced  to  the  same  degree  of  fineness.  This  difference 
necessitates  further  separation  and  treatment. 

Bolter. — The  bolter   (Fig.   15)   is  a  large  machine  containing 


FOOD   INDUSTRIES 


57 


some  360  sieves  made  of  silk  bolting  cloth  with  varying  mesh. 
The  machine  moves  with  a  side  motion  and  makes  from  eight  to 
twelve  separations  of  the  material.  The  fine  flour  is  thus  sepa- 
rated from  the  middlings  and  any  remaining  bran.  Separation 
gives  bran,  middlings  and  fines.  Fines  represent  flour.  All 
coarser  parts  again  go  through  the  purifier  and  smooth  roller 
repeatedly,  finally  being  separated  by  the  bolter.  When  the 


Fig.  16.— Bolting  Reel  for  Separating  the  Flour  from  the  Bran. 
(Courtesy  of  the  Washburn-Crosby  Co.,  Manufacturers  of  Gold  Medal  Flour.) 


separation  is  complete  the  flour  is  ready  to  be  automatically 
packed  in  bags  or  barrels.  The  germ  is  separated  out  by  the 
purifier  during  the  early  stages  of  the  refining  process  as  it  gives 
a  yellow  appearance  to  the  flour  and  impairs  its  keeping  qualities. 
Advantages  of  the  New  Process. — I.  Increased  capacity.  The 
roller-mill  has  greater  strength;  there  is  greater  centrifugal  force, 
the  mill  can  be  driven  faster. 


58  FOOD   INDUSTRIES 

II.  Much  less  power  is  required  to  run  the  machinery;  elec- 
tricity is  now  used. 

III.  Present  day  process  is  much  cleaner.     All  foreign  matter 
is   removed  in   different   siftings,   brushing  and   washing.     The 
purifier  showed  marked  progress  in  cleansing.     From  the  time 
that  the  grain  enters  the  mill  until  it  is  ready  for  shipment  as 
flour,  the  human  hand  does  not  touch  the  wheat.     It  is  carried 
from  place  to  place,  from  process  to  process  entirely  by  eleva- 
tors, conveyors  and  other  mechanical  devices. 

IV.  The  separation  is  much  more  perfect,  only  the  part  which 
is  desired  (the  endosperm)  is  found  in  flour. 

V.  It  is  much  more  economical  as  there  is  less  waste.     In  the 
old  process  much  that  was  valuable  was  carried  off  in  the  bran; 
the  working  over  this  material  again  and  again  saves  about  8  per 
cent,  on  each  bushel.     The  price  of  flour  is  cheaper  now  than  in 
former  years. 

VI.  Rollers  do  not  touch,  so  small  particles  of  steel  are  not 
often  found  in  flour.     Should  there  be  any,  they  can  be  removed 
by  passing  flour  through  a  magnetic  zone.     This  process  was 
thought  necessary  in  the  early  days  of  the  roller-mill,  but  it  is 
now  seldom  used. 

VII.  Modern  flour  keeps  better,  the  germ  has  been  removed 
and  there  is  less  heat  by  friction,  so  fewer  undesirable  changes 
take  place. 

Testing  of  Flour. — The  material  is  tested  at  different  stages  of 
the  process  and  again  on  the  finished  product  before  the  flour  is 
shipped.  Except  in  comparatively  few  mills  the  tests  are  very 
simple ;  usually  the  quality  is  told  by  texture,  color  and  by  making 
it  into  bread.  In  the  large  modern  mills  may  occasionally  be 
found  laboratories  where,  by  chemical  testing  of  the  various 
kinds  of  wheat  and  flour,  scientists  are  co-operating  with  the 
millers  in  the  production  of  finer  quality  flour.  The  chemist's 
advice  is  particularly  desirable  in  the  blending  and  mixing  of 
wheat  to  be  used  for  flour  making  and  in  the  manufacture  of 
cereal  products. 


FOOD    INDUSTRIES  59 

Wheat  Blends. — One  of  the  greatest  problems  that  the  miller 
has  to  meet  is  the  production  of  a  uniform  quality  of  flour.  A 
poor  grading  of  wheat,  or  even  changes  which  occur  in  the 
quality  of  the  grain  from  season  to  season,  necessitate  a  careful 
selection  of  wheats  for  blends  on  the  mill.  Wheats  must  be  so 
blended  that  the  "best  qualities  of  each  have  the  greatest  chance 
of  being  effective  in  the  resulting  flour."  A  careful  analysis  of 
various  wheats  as  to  their  starch  and  protein  content,  and  the 
determination  of  the  quality  of  the  gluten  in  flour,  greatly  assist 
in  the  blending  of  winter  and  spring  wheats  of  different  strength. 
Successful  blending  usually  insures  that  which  the  miller  most 
desires,  the  uniform  quality  of  his  products. 

Adulteration. — Many  substances  have  been  used  to  adulterate 
and  cheapen  flour.  The  most  common  custom  has  been  the 
grinding  of  foreign  matter  with  wheat  or  an  admixture  of  starch 
from  rye,  corn,  rice  or  potatoes.  Occasionally,  mineral  matter 
such  as  alum,  borax,  carbonate  of  magnesia  and  various  clays 
have  been  discovered.  The  United  States  Department  of  Agri- 
culture, however,  has  found  that  very  little  adulteration  of  any 
kind  has  been  practiced  in  this  country. 

Bleaching  of  Flour. — In  former  years  flour  was  artificially 
bleached  by  using  electrical  or  chemical  means  to  make  an  inferior 
article  resemble  a  superior  one.  While  this  custom  still  prevails 
in  some  countries,  the  bleaching  of  flour  has  been  forbidden  in 
the  United  States  under  the  Food  and  Drug  Act  for  interstate 
commerce. 

MILL   PRODUCTS. 

The  leading  mills  usually  put  out  as  many  grades  of  flour 
as  the  market  demands,  blending  spring  and  winter  wheat  of 
different  grades.  Generally  speaking,  flour  is  divided  into  four 
grades:  (i)  high  grade  patent;  (2)  bakers;  (3)  second  grade 
patent,  and  (4)  red  dog.  Red  dog  is  so  inferior  in  nutritive 
value  that  it  cannot  be  sold  as  food ;  it  is  used  largely  for  the 
making  of  paste. 

Flour  can  also  be  divided  into  hard  and  soft  varieties. 


60  FOOD   INDUSTRIES 

Hard  Wheat  Flour. — Hard  wheat  flour  is  made  from  spring 
wheat  and  represents  the  type  now  used  almost  universally  for 
bread-making.  It  is  rich  in  tissue  building  elements  and  gives 
the  largest  yield  of  gluten  so  necessary  in  the  making  of  a  light, 
porous  loaf  of  bread. 

Soft  Wheat  Flour. — This  flour  is  made  from  winter  wheat  and 
has  more  starch  and  less  gluten  than  hard  wheat  flour.  It  can 
be  utilized  for  bread-making,  but  it  is  less  nutritious  and  has  a 
poorer  flavor.  It  is  often  spoken  of  as  pastry  flour  and  is  used 
largely  for  the  making  of  cakes,  pastry,  crackers  and  the  so-called 
"quick  breads"  as  biscuit  and  muffins.  Soft  wheat  flour,  having 
less  gluten,  is  particularly  desirable  for  these  products. 

Spring  and  winter  wheat  flours  can  be  detected  by  simple 
experiments.  Hard  or  spring  wheat  flour,  on  account  of  its 
gluten  content,  absorbs  more  water,  has  a  gritty  feeling  and  is 
deeper  in  color,  having  a  yellowish  rather  than  a  white  appear- 
ance. Soft  wheat  flour,  having  a  large  percentage  of  starch, 
cannot  take  up  as  much  water;  it  forms  a  more  pasty  dough. 
It  is  white  and  has  a  soft  velvety  feeling  when  pressed  between 
the  fingers. 

Prepared  Flour. — This  product  is  a  so-called  "self-raising" 
flour  and  has  little  commercial  value.  It  consists  of  an  ordinary 
flour  mixed  with  other  flour  as  corn  and  rice,  salt  and  such 
ingredients  as  are  found  in  baking  powders,  as  bicarbonate  of 
soda  and  acid  potassium  phosphate.  The  addition  of  water 
causes  the  bicarbonate  and  acid  salt  to  unite  chemically  and 
carbon  dioxide  is  given  off.  This  gas  in  expanding  gives  a  light 
spongy  dough.  Prepared  flour  is  very  convenient  but  more 
expensive  than  ordinary  flour  and  baking  powder. 

Graham  Flour. — In  the  history  of  milling  there  is  still  another 
side  which  has  received  much  attention — how  much  of  the  wheat 
berry  should  be  utilized  as  food? 

In  primitive  milling  the  entire  kernel  except  the  husk  appeared 
in  the  flour,  but  the  refining  processes  of  modern  times  had 
reduced  this  to  the  use  of  the  endosperm  only.  During  the 
nineteenth  century  there  was  much  discussion  in  regard  to  the 


FOOD    INDUSTRIES  6 1 

starchy  nature  of  the  flour;  it  contained  only  8  per  cent,  protein 
and  3  per  cent,  mineral  matter.  This  was  the  kind  of  flour  that 
started  experimentation  by  Liebig,  which  resulted  in  the  produc- 
tion of  a  harder  variety  of  wheat.  Other  experimenters  were 
also  at  work  on  the  problem,  among  them  an  Englishman  by  the 
name  of  Graham.  Graham  was  a  great  temperance  worker.  In 
the  hope  of  curing  alcoholism,  he  recommended  a  change  in  diet, 
especially  advocating '  an  abstinence  from  meat.  To  supply  this 
deficiency  in  nitrogenous  matter,  he  suggested  the  use  of  bread 
having  a  higher  protein  percentage.  To  obtain  such  a  flour 
Graham  suggested  the  use  of  unbolted  wheat,  that  is,  the  use  of 
the  entire  wheat  berry.  This  was  practically  a  return  to  the 
earlier  method  of  milling  and  produced  a  bread  darker  in  color 
and  having  a  coarser  texture.  Much  agitation  of  the  question 
followed,  but  people  had  learned  to  prefer  white  bread,  and 
Graham  bread,  as  it  was  called,  never  became  popular  in  the  diet. 
On  investigation  by  scientists,  Graham  bread  was  found  to 
contain  more  protein  and  mineral  matter  than  white  bread,  but 
it  passed  through  the  intestines  more  rapidly.  At  that  time,  this 
was  thought  to  be  caused  by  the  mechanical  action  o.f  the  bran 
on  the  lining  of  the  intestines ;  the  bread  was  carried  away  before 
the  system  had  extracted  all  the  nutritive  matter  that  it  was  sup- 
posed to  yield.  Evidently  Graham  had  not  solved  the  question 
of  the  starchy  flour  of  his  day.  Liebig  was  far  more  fortunate, 
and  in  the  cultivation  of  hard  wheat  a  higher  percentage 'of  pro- 
tein has  been  obtained  than  was  found  in  the  original  Graham, 
flour. 

Entire  Wheat  Flour. — Just  before  the  introduction  of  the  Hun- 
garian method  which  so  improved  the  milling  process  another 
attempt  was  made  along  the  lines  Graham  had  worked.  This 
resulted  in  the  introduction  of  what  is  known  as  whole  or  entire 
wheat  flour.  This  flour  is  prepared  by  a  process  very  similar  to 
that  used  in  the  milling  of  Graham  flour,  except  that  after  the 
cleaning  processes  the  outer  bran  coats  are  removed  before  the 
berry  is  ground  into  flour.  Entire  wheat  flour,  therefore,  contains 
not  only  the  endosperm  but  the  layer  known  as  the  aleurone 


62 


FOOD    INDUSTRIES 


fl>  307.7  grams  of  bread  from  227  grains  of  Graham  flour;  b,  302.5  grams  of  bread  from 
227  grams  of  entire  wheat  flour;  c,  301.5  grams  of  bread  from  227  grams  of  standard 
patent  flour. 


a  b  c 

a,  Feces  from  Graham  bread  ;  d,  feces  from  entire  wheat  bread  ;  c,  feces  from  standard 

patent  bread. 

Fig.  17.— Bread  Made  from  Entire-wheat,  Patent,  and  Graham  Flours,  and  Character  of 
Feces  from  Same.     (Courtesy  of  the  U.  S.  Dept.  of  Agriculture.) 


FOOD   INDUSTRIES  63 

cells.    This  is  not  present  in  patent  flour,  being  removed  as  shorts 
or  middlings. 

Upon  investigation  it  has  been  found  that  entire  wheat  bread 
also  acts  as  a  laxative,  although  not  to  the  same  extent  as  Graham 
bread.  This  is  now  believed  to  be  due  to  the  peculiar  character 
of  the  protein  and  mineral  matter  of  the  aleurone  layer.  Possibly 
this  is  the  main  cause  in  Graham  bread,  although  it  was  for  a 
long  period  believed  to  be  entirely  due  to  the  action  of  the  bran 
coats.  Much  discussion  followed  as  to  the  relative  value  of 
entire  wheat  and  patent  flour.  As  regards  composition,  the 
difference  lies  entirely  in  the  protein  and  mineral  matter  of  the 
aleurone  layer.  Composition,  nevertheless,  does  not  tell  the 
whole  story,  for  the  important  question  is — how  much  of  the 
wheat  kernel  is  available  as  food?  White  flour  contains  the 
gluten  forming  proteins  which  are  the  most  important  and  be- 
lieved by  many  scientists  to  be  all  the  protein  that  is  available 
as  food  (Fig.  17).  Undoubtedly  the  claims  made  by  manufac- 
turers as  to  the  value  of  the  whole  wheat  flour  have  been  greatly 
over-estimated,  although  its  use  occasionally  gives  a  pleasant 
change  in  the  diet. 

Gluten  Flour. — Gluten  flour  is  a  substitute  for  patent  flour, 
much  used  by  people  having  diabetes  or  such  diseases  that  the 
use  of  starch  is  undesirable  in  the  diet.  It  is  prepared  from  an 
ordinary  good  grade  flour.  Flour  is  mixed  with  water  and 
allowed  to  stand.  In  time  the  starch  washes  out  and  if  allowed 
to  settle,  a  separation  can  be  made.  Repeated  washings  are  given 
until  the  starch  is  not  over  50  per  cent.  The  product  is  then 
dried  and  reduced  to  a  powder.  This  process  requires  time  and 
is  troublesome,  and  the  manufacturer  should  be  paid  for  his 
labor.  The  sale  price  for  such  flour  should  be  approximately 
22  cents  per  pound.  A  cheaper  product  is  sometimes  found  on 
the  market  selling  for  7  cents  per  pound.  Manufacturers  could 
not  afford  to  put  flour  through  this  process  and  sell  it  at  so  low  a 
figure;  cheap  gluten  flour  is  simply  a  low  grade  flour  containing 
bran. 

Cereal  Department. — Many  of  the  large  mills  have  a  cereal 


64  FOOD    INDUSTRIES 

department  where  the  so-called  breakfast  foods  are  manufac- 
tured by  processes  quite  similar  to  those  of  the  milling  of  flour. 
For  further  information  see  Chapter  VI,  Breakfast  Foods. 

Seminola. — The  preparation  from  wheat  of  a  coarse  meal 
known  as  "Seminola"  is  now  largely  carried  by  the  miller.  Semi- 
nola is  used  in  the  preparation  of  macaroni.  See  page  105. 

RYE. 

Rye  is  a  species  of  grain  resembling  wheat.  During  the 
Middle  Ages  it  furnished  much  of  the  bread  material  for  the 
great  body  of  people  in  Europe,  and  is  still  extensively  used  in 
Russia  and  Germany  by  the  peasantry,  although  it  is  gradually 
being  superseded  by  wheat.  Its  cultivation  is  evidently  not 
nearly  as  old  as  the  other  cereals,  for  there  is  no  mention  of  it 
in  ancient  languages.  It  was  known,  however,  to  the  Romans 
in  Pliny's  time. 

Rye  is  a  very  hardy  plant  and  will  grow  in  a  soil  too  poor  for 
the  majority  of  other  food  grains  and  too  cold  for  the  produc- 
tion of  wheat.  It  thrives  best  and  gives  the  largest  yield  under 
conditions  favorable  to  wheat.  The  varieties  grown  are  not 
nearly  as  great  as  the  other  cereals;  the  principal  varieties  are 
known  as  winter  and  spring  rye. 

Composition. — The  starch  content  is  much  like  that  of  wheat, 
a  difference  being  detected  only  in  the  microscopic  appearance 
of  the  granules.  The  nitrogenous  constituents  also  resemble 
wheat  as  far  as  gliadin  is  concerned.  There  is  no  protein,  exactly 
corresponding  to  glutenin ;  therefore,  the  gluten  formed  is  not 
altogether  similar  to  that  prepared  from  wheat  flour.  It  more 
closely  resembles  wheat  gluten,  however,  than  any  other  cereal 
and  can  be  successfully  used  with  or  without  a  leavening  agent 
for  the  making  of  bread. 

Uses. — Rye  ranks  second  as  a  world's  bread  material.  Rye 
bread  is  highly  nutritious,  but  is  less  pleasing  to  the  eye  than 
wheat  bread.  It  is  dark  in  color,  moist  and  compact  in  texture 
and  has  a  peculiar  sour  taste.  An  extreme  example  is  the  black 
bread  or  pumpernickle  of  North  Germany.  A  partial  rye  bread 


FOOD   INDUSTRIES  65 

is  often  made  by  mixing  the  flour  with  wheat  flour.  This  gives  a 
larger  yield  of  gluten  and  makes  a  larger  and  more  palatable 
loaf  of  bread.  Rye  flour  is  used  largely  in  the  United  States, 
but  chiefly  by  the  foreign  born  population. 

Rye  is  excellent  for  the  production  of  malt  used  in  the  dis- 
tillation of  spirits,  and  is  much  used  in  Europe  for  the  making 
of  gin  and  in  this  country  for  the  manufacture  of  whiskey. 

The  bran  can  be  used  as  a  cattle  food  and  the  straw  for  hats 
and  in  the  manufacture  of  paper. 

Adulteration. — The  adulteration  of  rye  flour  has  been  very 
frequent,  flour  of  other  cereals  being  added.  Such  admixture 
may  be  detected  with  the  use  of  the  microscope.  The  rye  granule 
as  a  rule  is  larger  than  wheat  and  frequently  has  characteristic 
markings  as  a  cross,  slit  or  star. 


CHAPTER  V. 


CEREALS. 

Biological  Origin. — The  botanist  places  cereals  as  belonging  to 
the  family  of  grasses,  the  long  cultivation  of  which  produces 
seeds  which  can  be  utilized  as  food.  The  word  cereal  can  be 
traced  to  Ceres,  the  name  of  the  Pagan  goddess  who  was  sup- 
posed to  preside  over  the  grains  and  harvests. 

Kinds. — The  most  important  are  wheat,  corn,  rice,  oats,  rye 
and  barley. 

Geographical  Distribution. — Cereals  are  extensively  cultivated 
in  all  parts  of  the  world  except  the  Arctic  region,  and  but  few 
countries  can  be  found  which  do  not  raise  grain  in  some  form 
as  a  staple  food.  The  reason  for  the  extensive  utilization  of 
these  cereal  foods  can  readily  be  seen. 

I.  Being  easily  grown,  they  are  comparatively  cheap. 

II.  There  is  little  refuse  as  compared  with  such  food  products 
as  meat,  fish  and  shell-fish. 

III.  They  contain  a  fair  proportion  of  nutritive  value. 

IV.  The  keeping  quality  is  excellent  if  the  cereals  are  properly 
protected  from  dust  and  insects.     On  account  of  their  dryness, 
they  are  not  readily  attacked  by  micro-organisms. 

V.  They  can  be  easily  prepared  for  the  table,  are  palatable  and 
when  properly  cooked  are  not  difficult  of  digestion. 

Use  in  Our  Country. — The  American  people  eat  a  great  quan- 
tity of  cereals.  This  is  a  natural  outcome  of  early  conditions  in 
this  country.  When  Columbus  landed  on  the  Western  Continent, 
he  found  the  native  tribes  had  a  cereal  under  extensive  cultiva- 
tion. This  the  early  settlers  called  corn,  the  European  name  for 
the  leading  cereal  food  of  the  country.  So  exclusively  was  this 
grain  grown  in  the  New  World  that  in  time  the  word  lost  its 
original  meaning  and  came  to  be  applied  only  to  Indian  corn  or 
maize. 

Columbus  is  supposed  to  have  carried  grains  of  corn  to  Europe 
on  his  first  return  voyage,  but  its  cultivation  there  spread  very 
slowly.  Although  introduced  into  Spain  at  the  end  of  the  fifteenth 


FOOD   INDUSTRIES 


67 


century,  it  did  not  reach  France  until  a  hundred  years  later. 
It  was  finally  carried  into  Asia  and  Africa  by  the  Portuguese. 
In  the  Western  World  it  advanced  with  the  progress  of  the  white 
race. 

AVERAGE  COMPOSITION  OF  (DRAINS  IN  DIFFERENT  FORMS 


Water 

Protein 

Fat 

Starch 

Fiber 

Ash 

Wheat  : 

12.0 

II.O 

1.7 

71.2 

2.2 

I.Q 

Meal  

12.  1 

12.9 

1-9 

70.3 

1.6 

1.2 

13.0 

9.5 

0,8 

75.3 

0.7 

0.7 

Oats  : 

10.  0 

10.9 

4-5 

59.1 

12.0 

3.5 

Meal                         •  -          .  .  .  . 

7.2 

IO.2 

7.3 

65.9 

3.5 

I.Q 

Rye: 

II.O 

IO.2 

2.3 

72.3 

2.1 

2.1 

Meal 

THoiir 

II.  2 

6.7 

0.9 

80.0 

0.8 

O.4 

Corn  : 

I2-5 

5-4 

68.9 

2.0 

1.5 

(  Old  orocess  • 

11.4 

8.5 

4.6 

72.8 

1.4 

1-3 

Meal{  New  process  

12.5 

6.8 

1.3 

78.0 

0.8 

0.6 

Rice  : 

12.0 

7.2 

2.0 

76.8 

1.0 

I.O 

Polished    •  •                              • 

12.4 

6.9 

0.4 

79-4 

0.4 

0.5 

Flaked  

II.7 

7.9 

°-5 

79.5 

0.4 

INDIAN  CORN  OR  MAIZE. 

Origin. — Indian  corn  or  maize  is  indigenous  to  the  tropical 
countries  of  America.  The  prevalent  opinion  is  that  it  was  a 
native  of  Central  America  and  Mexico,  and  that  it  passed  through 
the  same  stages  of  cultivation  and  dissemination  as  other  cereal 
foods.  It  resembles  the  sugar  cane  of  the  tropics  rather  than 
other  cereals  and  has  the  most  beautiful  and  luxuriant  growth  of 
all  the  grain  grasses. 

From  Central  America  it  is  supposed  to  have  spread  into 
South  America  traces  of  it  having  been  found  in  the  ancient 
tombs  of  Peru,  to  the  West  Indies  and  finally  into  North 


68  FOOD    INDUSTRIES 

America.  It  has  been  found  in  the  prehistoric  mounds  of  Ohio 
and  in  the  cliff  dwellings  of  the  southwest,  but  never  among  the 
remains  of  Egyptian  monuments,  thus  strengthening  the  belief 
that  it  is  solely  of  western  origin. 

Early  Cultivation. — Evidently  it  had  been  cultivated  long  and 
extensively  before  the  discovery  of  America,  for  by  the  time 
European  travelers  penetrated  into  the  New  World,  maize  was 
being  grown  by  most  of  the  North  American  Indians.  When 
Cartier  ascended  the  St.  Lawrence,  he  found  fields  of  it  where 
Montreal  now  stands.  The  early  chronicles  of  Virginia  and  other 
colonies  contain  many  descriptions  of  its  cultivation;  the  white 
man  first  receiving  this  food  from  the  Indian,  then  learning  the 
secrets  of  its  successful  growth  from  his  red  brother. 

The  climatic  conditions  seemed  to  have  been  particularly 
adapted  for  its  cultivation — an  abundant  rainfall  and  a  high  tem- 
perature during  the  growing  season.  We  read,  too,  in  history 
of  another  possible  reason  for  the  successful  growth  of  this 
cereal.  All  along  the  Atlantic  coast  the  Indians  made  a  practice 
of  fishing.  The  menhaden,  which  is  inedible,  was  placed  at  once 
on  the  corn  hills.  After  using  the  edible  varieties  of  fish,  it  was 
also  their  custom  to  put  the  bones  into  the  fields  for  fertilizing 
purposes.  Modern  scientists  have  discovered  that  these  bones 
contain  phosphates,  the  material  best  adapted  as  a  fertilizer  for 
corn. 

When  the  early  settlers  first  received  this  food  from  the 
Indian,  its  excellence  seemed  to  have  quickly  impressed  itself 
upon  them,  for  the  history  of  the  American  Colonies  was  after- 
wards closely  connected  with  the  cultivation  of  this  cereal. 

Varieties. — Popcorn,  flint,  dent  and  sweet  corn  represent  the 
chief  bulk,  although  there  are  some  seven  hundred  varieties  of 
corn  grown  in  the  United  States.  Most  varieties  have  white  or 
yellow  kernels,  but  various  other  colors  are  represented,  such  as 
black,  blue  and  red. 

Early  Methods  of  Preparation. — Hulled  corn  was  used  early  by 
the  colonists  and  in  time  became  one  of  our  typical  American 
foods,  especially  among  the  natives  of  New  York  and  the  New 


FOOD   INDUSTRIES  69 

England  States.  Corn  was  taken  in  its  dry  state  and  immersed 
for  several  hours  in  a  solution  of  wood-ash  called  lye.  In  time 
the  outer  coat  became  soft  and  could  be  removed  by  gently 
stirring  without  impairing  the  inner  part.  After  careful  wash- 
ing to  remove  the  alkali  it  was  ready  for  a  long,  slow  process  of 
cooking.  The  method  of  cooking  used  was  an  old  Indian  custom 
and  strongly  resembled  our  tireless  cooker  of  to-day.  Large 
stones  were  thoroughly  heated  by  means  of  a  fire  and  when 
sufficiently  hot  were  piled  around  the  utensil  holding  the  corn. 
Along  the  coast  seaweeds  were  used  to  cover  it.  The  corn  was 
kept  in  this  heat  until  it  was  ready  to  be  eaten. 

Old  Milling  Method. — The  early  colonial  records  tell  us  that 
the  Indians  pounded  corn  after  parching  it  before  an  open  fire. 
The  handstones  or  "corn"  stones  were  of  the  mortar  and  pestle 
type,  closely  resembling  those  used  by  primitive  people  the  world 
over.  Many  of  these  ancient  stones  have  been  found  near  the 
Indian  settlements  in  Texas  as  well  as  other  parts  of  the  United 
States.  After  crushing  the  corn  to  a  coarse  meal,  sometimes 
nuts  and  berries  or  bits  of  meat  and  fish  were  added.  The 
colonists  took  very  kindly  to  this  dish  as  it  closely  resembled 
Scotch  oatmeal  where  meat  broth  was  added. 

Samp,  Hominy  and  Cornmeal. — Very  early  in  the  history  of 
the  colonial  days,  samp  was  placed  upon  the  market.  It  was  pre- 
pared by  a  purely  mechanical  method  by  which  the-  hull  and  germ 
were  separated  out  by  a  process  of  cracking  and  sifting.  Samp 
is  the  edible  part  of  the  corn;  it  is  practically  the  whole  kernel 
minus  the  germ  and  hull.  When  coarsely  ground  it  appears  as 
hominy.  The  maize  kernel  was  also  ground  between  stones, 
bolted  to  remove  the  bran,  and  a  meal  thus  produced  which  could 
be  used  directly  as  human  food.  Hominy  or  cornmeal  could  be 
boiled  as  hominy,  mush  or  hasty  pudding  or  baked  as  hoe-cake, 
johnny  cakes,  corn-bread  and  muffins. 

Modern  Milling. — Modern  milling  operations  have  greatly 
changed  the  method  of  producing  cornmeal  and  flour.  Corn 
after  being  carefully  cleaned  is  kiln  dried  to  remove  moisture, 
crushed  between  grooved  mill-stones  to  desired  fineness  or  ground 


7O  FOOD    INDUSTRIES 

between  cylinders,  and  sifted  to  remove  particles  of  bran.  Not 
only  is  the  outer  bran  removed  much  more  carefully  than  in 
former  years,  but  to  a  large  extent  the  germ  also.  This  is  par- 
ticularly true  of  flour  meant  for  exportation,  thus  avoiding 
changes  of  a  deleterious  nature  taking  place  during  transporta- 
tion. In  corn  the  greater  part  of  the  fat  occurs  in  the  germ 
which  in  time  is  apt  to  become  rancid.  The  removal  is,  therefore, 
a  distinct  advantage  as  far  as  the  keeping  quality  is  concerned, 
but  it  greatly  impairs  the  palatability  and  nutritive  value  of  the 
prepared  meal.  Dr.  H.  W.  Wiley  claims  that  "Refined  Indian 
meal  has  lost  three-fourths  of  its  fat,  a  large  proportion  of  its 
mineral  matter  and  also  a  very  considerable  portion  of  its  pro- 
tein, due  to  the  separation  of  the  bran  which  is  extremely  rich 
in  protein  and  the  germ  which  is  rich  in  oil  and  protein." 

The  color  of  cornmeal  and  flour  depends  on  the  color  of  the 
variety  of  corn  used,  white  or  yellow.  It  is  coarse  or  fine  accord- 
ing to  the  process  employed  in  milling. 

Uses. — I.  Food  for  Man. — Indian  corn  is  the  leading  cereal  of 
this  country.  It  is  grown  in  all  kinds  of  soil  and  under  favorable 
conditions  produces  a  large  yield.  Maize  is  lower  in  protein  than 
wheat  and  oats,  but  fully  equal  to  other  cereals  in  that  respect 
and  contains  a  larger  proportion  of  fat  than  most  of  the  grains. 
It  is  a  food  well  adapted  to  those  engaged  in  hard,  manual  labor, 
as  it  yields  a  comparatively  high  amount  of  energy.  Throughout 
the  country  it  is  used  as  food,  but  more  extensively  in  the  South 
where  Indian  corn  is  served  in  some  form  daily  at  one  or  more 
meals. 

As  a  garden  vegetable,  it  is  raised  in  large  quantities  for  the 
market  to  be  eaten  on  the  cob  or  boiled  with  beans  as  succotash. 
The  canning  of  corn  is  an  important  industry  in  some  states, 
especially  Maine  and  New  York. 

Popcorn  is  used  largely  throughout  the  states  as  a  delicacy. 
It 'is  a  specially  hard  variety  which  has  the  property  of  the  com- 
plete turning  inside  out  of  the  kernel  on  the  application  of  heat. 

Corn  is  also  used  as  before  stated,  either  cracked  or  crushed 
as  hominy  and  finely  ground,  either  bolted  or  unbolted  as  meal  or 


FOOD    INDUSTRIES  71 

flour.  On  account  of  the  inability  of  the  nitrogenous  constituents 
to  form  gluten,  corn  flour  cannot  be  utilized  for  bread-making 
unless  it  is  mixed  with  a  large  proportion  of  wheat  flour. 

II.  As  food  for  cattle,  corn  silage  is  extensively  used  as  well 
as  the  green  and  dried  grain. 

III.  Cobs  furnish  a  fuel  and  are  also  used  in  the  manufacture 
of  tobacco  pipes. 

IV.  On  account  of  its  porosity  and  its  power  of  absorption, 
pith  of  corn  is  used  in  the  construction  of  war  vessels,  compressed 
blocks  of  it  being  placed  behind  the  outer  armor,  where  in  case 
of    its   being   pierced   during   battle    the   water    will   be   quickly 
absorbed.     Pith  is  also  used   for  making  varnishes,,  gun-cotton 
and  other  explosives. 

V.  The  husks  are  used  in  many  country  places  for  the  making 
of  mattresses. 

VI.  It  is  largely  used  in  the  preparation  of  alcohol  and  alco- 
holic beverages. 

VII.  The  kernel  which  contains  the  starch  in  comparatively 
large  amounts  furnishes  the  source  of  supply  for  most  of  the 
American    Starch    Industry.      For    further   information   on   this 
subject  see  Chapter  IX,  Starch  and  Allied  Industries. 

Adulteration. — Practically  no  adulteration  of  corn  products  has 
been  found  by  the  United  States  Department  of  Agriculture. 

RICE. 

Origin. — Rice  has  been  cultivated  from  times  immemorial,  but 
it  is  supposed  to  have  originated  from  the  wild  variety.  Mention 
is  made  of  its  cultivation  in  China  as  early  as  2800  B.  C.  It  is 
undoubtedly  of  Eastern  origin,  for  we  find  it  early  appearing  in 
India  and  Japan  as  a  staple  food  and  allusion  is  made  to  its  use 
in  the  Talmud.  It  is  supposed  to  have  been  introduced  into 
Persia  from  Southern  India  and  later  carried  by  the  Arabs  into 
Spain.  Although  it  was  raised  in  Southern  Europe  in  the  fifteenth 
century  it  was  not  introduced  into  the  United  States  until  1694 
when  the  captain  of  a  sailing  vessel  from  Madagascar  presented 
a  bag  of  "paddy"  rice  to  a  Charleston  merchant.  It  soon  became 
6 


72  FOOD    INDUSTRIES 

an  important  industry  of  South  Carolina  and  continued  as  such 
until  the  breaking  out  of  the  Civil  War. 

Geographical  Distribution. — It  is  now  grown  extensively  in 
India,  China,  Japan,  Southern  Europe  and  in  our  own  Southern 
States,  particularly  the  South  Atlantic  and  Gulf  Section.  Caro- 
lina produces  the  best  rice,  large  amounts  being  also  grown  in 
Louisiana  and  Texas. 

Composition. — Rice  is  rich  in  starch,  poor  in  protein,  fat  and 
mineral  matter.  In  the  East  the  deficiency  of  protein  is  supplied 
by  the  addition  of  leguminous  plants,  a  combination  of  rice  and 
legumes  being  a  cheaper  complete  food  than  wheat  and  meat. 
South  Carolina  and  Japanese  rices  are  richer  in  fat  and  are, 
therefore,  highly  prized  among  rice  eating  nations. 

Cultivation. — Rice  is  the  most  extensively  cultivated  of  the 
grains,  furnishing  the  principal  food  cereal  for  over  one-third 
of  the  human  race.  Where  dense  populations  are  dependent  upon 
an  annual  crop,  rice  has  been  chosen  wherever  the  climate  per- 
mits, as  it  is  the  most  prolific  of  all  crops.  It  will  grow  best  on 
Soil  ill  adapted  for  any  other  grain.  Sub-tropical  rather  than 
tropical  climate  gives  the  largest  yield.  It  requires  a  moist  soil 
artificially  flooded  at  certain  seasons.  The  fields  are  often 
so  wet  that  workmen  may  sink  to  their  knees.  It  grows  most 
freely  on  lowlands,  especially  on  land  which  can  be  flooded,  but 
it  can  also  be  raised  on  upland  fields.  Japan  grows  large  quan- 
tities of  rice  on  terraces  of  hills  and  mountain  sides  by  flooding 
from  reservoirs  built  on  a  higher  elevation. 

Milling. — Primitive  methods  for  milling  rice  were  very  simple 
and  are  still  in  common  use  in  many  of  the  oriental  countries. 
Rough  rice  was  placed  in  a  hollow  stone  and  pounded  with  a 
pestle  until  the  hull  and  cuticle  were  sufficiently  loosened  to  be 
removed  by  the  process  of  winnowing.  A  hollow  block  of  wood 
was  afterwards  substituted  for  the  stone,  a  wooden  pestle  or 
pounder  as  it  was  called  being  so  arranged  above  the  block  that 
the  pounder  would  fall  into  the  rice  tub  when  operated  by  the 
miller.  Water  power  in  time  was  used  and  finally  modern 
machinery  and  methods  were  introduced. 


FOOD   INDUSTRIES  73 

The  object  of  modern  milling  is  to  produce  from  rough  or 
"paddy"  rice,  a  rice  for  the  market  which  has  been  not  only  thor- 
oughly cleaned  and  the  husk  and  cuticle  removed,  but  having 
the  inner  surface  polished.  To  accomplish  this,  rice  must  pass 
through  a  long  and  complicated  process. 

I.  Rough  rice  is  screened  to  remove  dirt  and  foreign  material 
of  all  kinds. 

II.  Chaff   is    loosened   by    rapidly    revolving   mill-stones   and 
removed  by  screening.     This  sifting  also  causes  a  separation  of 
whole  and  broken  grains. 

III.  The  outer  skin  is  removed  by  pounding  in  a  huge  mortar 
with  a  pestle.     By  screening  a  separation  is  made  of  the  clean 
rice  and  flour. 

IV.  The  clean  rice  has  become  heated  through  friction  so  must 
remain  in  cooling  bins  for  8  or  9  hours.    After  passing  through 
brush  screens  to  remove  the  last  of  the  rice  flour,  rice  is  ready 
for  the  final  process  of  polishing. 

V.  Polishing  is  done  by  friction  with  moosehide  or  sheepskin. 
This  process  gives  to  rice  its  pearly  appearance  and  satisfies  the 
demands  of  fashion.     It  is  a  blunder;  however,  from  the  stand- 
point of  food  value  as  much  nourishment  is  lost  in  the  removal 
of  nearly  all  of  the  fat  during  the  polishing  process.    Unpolished 
rice  is  more  economical,  has  greater  food  value  and  has  a  richer 
taste  which  makes  the  rice  served  in  oriental  countries  so  much 
superior  to  the  grain  here. 

Adulteration. — The  adulteration  of  rice  is  confined  to  coating 
the  grains  with  paraffin,  talc  or  glucose.  The  object  is  to  give 
a  better  appearance  to  the  grain  and  protect  it  from  insects. 

Uses. — I.  Rice  as  a  food  furnishes  a  starch  supply  which  is 
easily  digested  and  is  useful  in  disordered  conditions  of  the  di- 
gestive tract  when  many  solid  foods  cannot  be  borne.  In  rice- 
growing  countries  it  is  used  as  a  substitute  for  wheat  bread  and 
potatoes.  Rice  flour  cannot  be  used  for  bread-making  and  is 
seldom  used  for  cake  but  mixed  with  wheat-flour  it  gives  white- 
ness to  bread. 

II.  A  large  proportion  of  the  rice  taken  to  Europe  is  used 


74  FOOD    INDUSTRIES 

for  starch-making,  rice  starch  being  used  in  laundries  and  mus- 
lin factories. 

III.  It  is  the  source  of   a  drinking  spirit  in   India  and  the 
national  beverage  of  Japan  is  prepared  from  the  grain  by  means 
of  a  ferment.     In  both  Europe  and  America  rice  is  used  by  the 
distillers  of  alcohol  and  it  is  often  employed  in  beer-making. 

IV.  Rice  straw  is  used  as  a  cattle  food  and  as  a  material  for 
bonnets. 

V.  Rice  polish  or  the  fine  flour  resulting  from  the  polishing 
process  is  utilized  as  a  food  stock  especially  for  cows  and  pigs. 

VI.  Rice   hulls  are  used  as   fertilizers  and   also   for  packing 
around  breakable  articles. 

OATS. 

Oats  furnish  a  more  important  food  material  for  human  be- 
ings in  Europe  than  in  America,  the  largest  amount  being  con- 
sumed in  the  British  Isles.  Their  chief  use,  however,  both 
abroad  and  here  is  for  cattle  food  especially  for  horses.  The 
plant  furnishes  green  forage,  hay  and  straw  as  well  as  the  milling 
products. 

Composition. — Unlike  rice,  oats  are  particularly  rich  in  nitro- 
genous constituents  and  mineral  matter.  They  are  highly  es- 
teemed as  a  food  for  the  building  and  restoration  of  tissue.  Oats 
contain  more  fat  than  any  other  cereal  closely  resembling  Indian 
corn  in  this  respect. 

Oatmeal. — As  a  human  food,  oats  appear  on  the  market  as 
oatmeal  or  "groats."  Many  varieties  are  cultivated  for  the  prepa- 
ration of  oatmeal  but  in  general  character  they  bear  a  close 
resemblance  to  one  another.  The  outer  husk  is  closely  adherent 
to  the  grain  and  cannot  be  entirely  separated  from  the  kernel  by 
the  ordinary  method  of  grinding.  Old  fashioned  oatmeal,  there- 
fore, consisted  of  not  only  the  kernel  but  a  great  deal  of  cellu- 
lose in  the  form  of  small,  sharp  particles.  These  acted  as  a 
stimulant  to  the  intestines,  irritating  to  some  people. 

On  account  of  the  large  amount  of  fat,  oatmeal  is  often  spoken 
of  as  a  "heating  food"  and  its  use  is  discouraged  during  the 
summer  months.  In  the  American  diet,  however,  oatmeal  is 


FOOD    INDUSTRIES  75 

not  eaten  often  or  in  large  amounts  so  this  cannot  be  a  serious 
consideration.  Oatmeal  is  probably  the  most  nutritious  of  the 
cereal  foods,  but  it  seems  to  have  a  peculiar  heating  effect  on 
some  people,  causing  skin  eruption.  The  cause  of  this  is  not  cer- 
tain, some  claiming  it  to  be  caused  by  the  protein,  others  attribu- 
ting it  to  a  special  constituent  found  in  oatmeal. 

Milling. — In  the  manufacture  the  grain  is  thoroughly  cleaned 
to  remove  foreign  material  of  all  kinds,  kiln-dried  to  loosen 
the  outer  husk  anti  to  develop  flavor,  then  screened  to  remove 
husks.  The  kernel  thus  freed  is  called  groats.  All  forms  of 
oatmeal  are  produced  from  these  groats.  For  further  informa- 
tion see  Chapter  VI.  Breakfast  Foods. 

Adulteration. — The  adulteration  of  oatmeal  is  not  frequent,  as 
the  price  of  this  cereal  is  so  low  that  the  substitution  of  other 
grains  would  not  be  profitable. 

BARLEY. 

Origin. — Barley  is  generally  supposed  to  have  originated  from 
the  wild  species  native  to  Western  Asia.  According  to  Pliny 
it  is  one  of  the  earliest  of  cereals  in  the  diet  of  mankind.  It  has 
been  found  in  the  lake  dwellings  of  Switzerland,  in  deposits  be- 
longing to  the  Stone  Age  and  in  the  earliest  Egyptian  monuments. 
It  is  spoken  of  in  the  Books  of  Moses  and  early  Greek  and 
Roman  writers  make  many  references  to  it.  The  Greeks  are 
supposed  to  have  trained  their  athletes  on  this  cereal  and  the 
sacred  barley  of  antiquity  figured  on  many  of  the  ancient  coins. 

Cultivation. — The  cultivation  of  barley  is  somewhat  similar  to 
that  of  wheat  so  far  as  soil  is  concerned.  It  is,  however,  con- 
sidered the  most  hardy  of  all  the  cereal  grains,  its  limit  extend- 
ing farther  north  than  the  others  and  reaching  as  far  south  as  the 
sub-tropics.  It  has  been  grown  successfully  in  Ireland,  Norway 
and  Alaska  and  in  Egypt,  India  and  Algeria. 

Composition. — Barley  contains  all  the  nutritive  properties  of 
the  other  cereals.  It  contains  less  protein  and  carbohydrate  than 
wheat,  but  has  more  fat  and  mineral  matter. 

Use. — Until  comparatively  recent  years,  barley  formed  an  im- 
portant article  of  diet  in  most  of  the  northern  countries  and  it 


76  FOOD    INDUSTRIES 

is  still  largely  used  in  Northern  Europe  among  the  peasantry. 
In  England  it  was  the^  leading  cereal  of  the  early  days,  the  tra- 
ditional goose-pie  and  bag-pudding  of  the  Christmas  feast  being 
made  of  this  cereal.  It  was  used  until  very  recently  by  90  per 
cent,  of  the  laboring  class,  but  wheat  has  gradually  taken  its 
place  throughout  Great  Britain  although  barley  cakes  are  still  to 
some  extent  eaten. 

In  Japan  rice  is  generally  supposed  to  be  the  only  cereal,  but 
barley  is  largely  used  among  the  poorer  classes,  a  social  line  be- 
ing drawn  between  the  rice-eating  and  barley  eating  natives.  It 
is  also  much  used  among  the  Hebrews  as  a  breakfast  food  and 
pudding. 

Medically  barley  is  rated  as  the  mildest  of  the  cereals  and  in 
various  forms  it  is  found  often  in  invalid  dietaries. 

In  the  Old  World  it  is  grown  extensively  for  horses,  cattle 
and  pigs,  the  hay  and  straw  being  utilized.  In  the  United  States 
it  is  grown  in  the  northern  and  western  parts  to  some  extent  for 
hay,  but  its  chief  use  is  for  making  fermented  beverages.  It  is 
not  utilized  to  any  extent  as  a  human  food,  although  it  is  some- 
times used  in  domestic  cookery  as  an  ingredient  of  soups  and 
broths. 

Mill  Products. — About  the  only  products  milled  are  meal  and 
pearl  barley.  Barley  meal  is  the  whole  grain  cleaned,  deprived 
of  its  outer  husk  and  ground.  In  this  form  it  is  sometimes  sold 
to  the  manufacturer  of  beer.  Pearl  barley  has  the  outer  and 
inner  husk  removed,  is  ground  to  a  round  form  and  put  through 
a  polishing  process.  As  a  food  it  is  used  mostly  in  this  form  for 
thickening  soups,  making  cool  drink  for  invalids  and  for  infant 
feeding. 


CHAPTER  VI. 


BREAKFAST   FOODS  AND   COFFEE  SUBSTITUTES. 

A  canvass  of  our  markets  would  reveal  to-day  an  endless 
variety  of  cereals  listed  under  the  name  of  breakfast  foods.  In 
the  early  days  of  America,  the  only  cereals  utilized  to  any  extent 
were  wheat  as  wheat  flour  and  corn  as  samp,  hominy,  cornmeal 
and  hulled  corn.  In  New  England  the  custom  prevailed  of  using 
popcorn  as  a  breakfast  food.  Bread  crumbs  were  also  fre- 
quently toasted  and  used  for  that  purpose.  Oatmeal  was  later 
introduced  by  the  Irish  and  Scotch  immigration  and  finally  bar- 
ley, rye  and  rice,  but  their  use  has  always  been  more  or  less  lim- 
ited to  the  foreign  born  population. 

It  was  not  until  the  latter  part  of  the  iQth  century  that  a  new 
interest  was  awakened  in  this  class  of  foods.  Much  experi- 
menting was  done  on  the  cereals,  new  methods  of  manufacture 
were  developed  and  many  new  products  were  placed  on  the  mar- 
ket listed  under  the  name  of  "The  Cereal  Breakfast  Foods." 
Probably  no  class  of  foods  has  ever  been  so  extensively  arid  in- 
geniously advertised.  In  a  comparatively  short  time  a  bewild- 
ering variety  could  be  purchased  in  the  local  markets ;  many  ap- 
peared to  remain  indefinitely,  but  a  far  larger  number  soon  could 
be  found  only  in  forgotten  places.  This  constant  and  ever  in- 
creasing variety  of  breakfast  foods  is  giving  to  the  cereals  an 
important  place  in  the  dietary  which  was  not  known  in  the  past 
history  of  our  country. 

Classification. — Although  the  list  of  these  foods  is  so  long  and 
varied,  they  fall  very  readily  into  four  classes. 

/Whole  grain. 
I.  Uncooked^ 

^Part  of  grain. 
II.  Partly   cooked. 

III.  Cooked. 

IV.  Malted. 

The  grains  commonly  used  in  this  country  are  oats,  wheat, 
corn  and  to  some  extent  barley  and  rice.  In  the  majority  of 


78  FOOD    INDUSTRIES 

breakfast  foods,  only  one  variety  of  grain  appears,  at  other  times 
two  or  more  are  mixed.  Breakfast  foods  are  prepared  directly 
from  these  cereals,  either  by  mechanical  manipulation,  culinary 
processes  or  malting.  Many  times  such  changes  are  brought 
about  in  order  to  make  the  product  ready  either  for  immediate 
consumption  or  for  serving  after  a  moderate  amount  of  cook- 
ing. These  changes  in  composition  usually  consist  in  the  more 
or  less  complete  rupturing  of  the  starch  granule  and  sometimes 
bring  about  its  conversion  into  more  soluble  forms.  Otrur  sub- 
stances of  the  nature  of  condiments  are  often  added  as  maple- 
sugar,  cane  sugar  and  salt.  Particular  methods  of  preparation 
are  usually  trade  secrets. 

I.  Uncooked. — The  whole  grain  variety  is  best  represented  by 
oatmeal.     This  is  practically  the  old-fashioned  cereal  with  mod- 
ern methods  of  preparation.     Ingenious   devices  have  been  in- 
vented  for  the  removal  of   foreign  seeds,   dirt   and  other  sub- 
stances of  an  undesirable  nature.     The  roller  process  is  now  used 
instead  of  the  old  idea  of  crushing  but  the  roller  is  supposed  only 
to  take  off  the  outer  husks.     They  are  removed  now  quite  thor- 
oughly so  the  amount  of  cellulose  left  is  much  smaller  than  for- 
merly.    Sometimes  there  is  a  gradual  reduction  of  the  kernel  so 
oatmeal  may  be  in  the  granulated  form.     This  is  more  common 
in  Canada  than  in  the  United  States. 

Varieties  consisting  of  parts  of  grain  may  be  found  in  farina 
and  cream  of  wheat.  They  are  prepared  from  the  hard,  granu- 
lated particles  of  wheat  usually  taken  from  the  first  or  second 
break  in  the  manufacture  of  flour.  It  is  the  part  of  wheat  from 
which  patent  flour  is  made.  This  class  of  breakfast  foods  is 
usually  made  from  hard  spring  wheat  as  soft  winter  wheat  is  apt 
to  break  down  too  finely. 

The  uncooked  cereals  are  sold  at  a  lower  price  as  there  has 
been  less  manipulation  by  the  manufacturer.  They  require, 
however,  a  longer  cooking  in  the  home. 

II.  Partly  Cooked. — By  far  the  largest  number  of  the  break- 
fast foods  of  to-day  belong  to  this  class ;  90  per  cent,  of  the  oat- 
meal consumed  in  the  United  States  is  in  this  form,  on  account 


FOOD   INDUSTRIES  79 

of  its  easy  preparation  in  the  home.  The  first  of  these  cereals 
to  be  introduced  was  the  rolled  oats.  The  preliminary  treat- 
ment of  cleaning,  kiln-drying  and  hulling  is  practically  the  same 
as  with  the  uncooked  varieties.  The  "groats"  then  pass  through 
a  process  of  steaming  and  while  still  wet  go  to  heated  rolls 
which  flatten  them  into  flakes.  Additional  cleaning  processes 
are  sometimes  used  to  loosen  and  remove  the  fine  particles  of 
floury  matter  before  the  flakes  are  put  into  packages.  Almost 
all  of  the  grains  are  now  being  flaked,  while  peas  and  beans  are 
also  found  in  the  Canadian  market. 

Originally  this  process  of  steaming  was  thought  to  cook  the 
grain  so  thoroughly  that  only  a  few  minutes  were  necessary  in 
the  home.  It  is  now  known  that  the  heat  has  not  been  applied 
long  enough  and  such  cereals  need  to  be  thoroughly  recooked 
before  serving.  Less  water  is  needed  as  much  has  been  absorbed 
in  the  steaming  process.  On  account  of  the  flattened  condition 
of  the  grain  exposing  more  surface  it  is  not  necessary  to  give  as 
long  a  time  as  in  uncooked  cereals.  More  time,  however,  should 
be  allowed  than  is  stated  on  the  package. 

III.  Cooked. — The  ready  to  serve  varieties  are  numerous  and 
are  prepared  in  various  ways.  The  most  common  forms  are: 

1.  The  flaked  cereals  closely  resembling  the  rolled  variety,  but 
heat  has  been  continued  for  a  longer  time.    They  sometimes  con- 
sist of  one  cereal  as  flaked  rice  or  they  may  be  combinations  of 
grain  as  wheat  and  barley.     Other  substances  such  as  syrup  and 
salt  are  frequently  added  and  some  flaked  varieties  have  passed 
through  an  additional  process  of  parching  or  toasting,  thus  giv- 
ing them  a  darker  color  and  producing  a  flavor  which  is  relished 
by  most  people.     Several  of  these  flaked  varieties  as   Cranose 
Flakes  and  Force  were  patented  at  Battle  Creek,  Michigan,  the 
center  for  the  development  of  breakfast  foods,  and  were  among 
the  earliest  of  the  ready-to-eat  foods. 

2.  The  puffed  variety,  as  Puffed  Rice,  is  made  by  placing  the 
grain  in  sealed  cylinders  which  are  kept  revolving  at  a  tempera- 
ture of  approximately  550  F.  for  an  hour.     The  moisture  within 
the  grain  turns  to  steam,  which  on  being  released  suddenly  from 


So  FOOD   INDUSTRIES 

the  cylinders  causes  an  explosion  of  the  starch  granule  and  a 
puffing  up  of  the  cereal  grain. 

3.  There  is  but  one  example  of  the  shredded  variety,  but  so 
popular  'is  it  among  Americans  that  it  stands  in  a  class  by  itself. 
"Shredded  Wheat  Biscuit"  as  it  is  called,  was  the  first  breakfast 
food  to  appear  on  the  market  made  from  wheat.     Its  manufac- 
ture dates  from  1895.     The  whole  wheat  kernel  appears  in  the 
product   and   special   machinery   is   needed   for   its   preparation. 
After    a    thorough    cleaning    the    cereal    passes    through    some 
twenty  to  twenty-five  different  processes,  the  most  important  of 
which  are  the  following:   1st.  the  whole  wheat  is  steam-cooked 
for  about  thirty-five  minutes  without  being  flavored  then  dried 
to   remove  excessive  moisture;   2nd.   by   special   machinery  the 
grains  are  drawn  into  shreds  which  are  piled  in  layers,  cut  into 
miniature  loaves  and  baked. 

4.  Variety  resembling  crumbs,   as   Grape-Nuts.     This  break- 
fast food  is  prepared  from  wheat  and  barley  ground  together, 
made  into  a  flour,  kneaded  into  bread  dough  and  baked.     The 
bread  is  then  toasted  and  crushed.     Grape-Nuts  has  had  a  very 
large  sale  in  the  United  States,  Canada  and  England  for  a  num- 
ber of  years  and  is  now  gradually  being  introduced  in  the  com- 
mercial centers  of  foreign  lands. 

IV.  Malted  Preparations. — The  cereal  grains  are  all  rich  in 
starch  and  on  account  of  the  hard  impervious  nature  of  the  walls 
of  the  starch  granules  such  food  is  not  easy  of  digestion  in  the 
raw  state.  A  long  slow  cooking  is  necessary  not  only  to  rupture  the 
granule,  but  to  make  the  starch  more  soluble.  The  digestive 
fluids  under  ordinary  conditions  can  then  readily  take  care  of 
such  a  product.  To  further  aid  digestion  it  was  suggested  sev- 
eral years  ago  that  the  cereal  starch  be  subjected  to  the  action  of 
malt.  Malt  contains  an  enzyme  called  diastase  which  has  the 
power  of  rapidly  liquifying  starch  after  the  cell  walls  have  been 
ruptured  and  then  converting  it  into  dextrin  and  maltose.  Mal- 
tose is  soluble  and  several  steps  nearer  the  completion  of  the  di- 
gestive process.  The  amount  of  starch  which  has  been  changed 
to  dextrin  and  maltose  depends  upon  the  thoroughness  with 


FOOD   INDUSTRIES  8 1 

which  the  malting  process  has  been  conducted.  Manufacturers 
of  these  products  claim  that  the  process  has  been  thorough  and 
these  cereals  are  highly  recommended  for  people  with  weak  di- 
gestion. It  is  a  question  whether  this  claim  is  always  true  or 
whether  malt  has  simply  been  added  to  give  flavor  after  the 
cereal  has  been  cooked  with  dry  heat.  Heat  would  readily 
change  starch  to  dextrin  without  the  aid  of  diastase  and  is  a 
much  quicker  process  than  that  of  malting.  For  information  as 
to  the  malting  process  see  Chapter  XI,  Alcoholic  Beverages. 
Such  a  cereal  has  a  pleasant  taste  relished  by  many  people  and 
adds  variety  to  the  diet,  but  it  is  not  predigested. 

Experiments  along  this  line  have  been  carried  out  at  the 
Iowa  Experiment  Station  on  a  number  of  malted  breakfast 
foods.  It  is  difficult,  however,  to  decide  whether  the  malting 
process  has  actually  been  carried  out  or  whether  malt  has  been 
added,  but  there  are  strong  evidences  to  make  scientific  men 
feel  that  in  many  cases  the  cereal  has  been  cooked  by  dry  heat. 
The  term  malted  is  often  used  when  malt  has  simply  been  added, 
as  malted  milk.  Milk  cannot  be  malted  in  the  sense  of  adding 
diastase  to  it ;  it  can  only  be  reduced  to  the  powdered  form  then 
mixed  with  ground  barley  malt.  Much'  has  been  said  of  the  ad- 
vantage of  using  predigested  foods  in  order  to  relieve  the  diges- 
tive tract  of  much  of  its  normal  work.  It  is  a  question,  how- 
ever, as  to  the  wisdom  of  taking  habitually  artificially  digested 
foods.  The  human  body  under  normal  conditions  is  well  fitted 
to  perform  this  work  for  itself  and  the  digestive  organs  need  a 
certain  amount  of  exercise  to  keep  them  in  proper  condition.  It 
has  often  been  quoted  "A  well  man  has  no  more  need  of  predi- 
gested food  than  a  sound  man  has  of  crutches."  These  cereals, 
therefore,  should  be  taken  more  for  their  pleasant  taste  and  to 
give  variety  than  for  their  so  called  predigested  value. 

Adulteration. — While  in  advertising  much  has  been  said  greatly 
over-estimating  the  virtues  .  of  the  breakfast  foods,  the  experi- 
^ment  stations  and  pure  food  examiners  have  discovered  very 
little  adulteration.  Manufacturers  as  a  rule  use  good  whole- 
some material,  processes  are  modern  and  conditions  at  the  fac- 


82  FOOD    INDUSTRIES 

tories  most  sanitary.  Goods  are  protected  while  in  the  dealers' 
hands  and  are  so  packed  that  they  can  easily  be  taken  care  of  by 
the  householder. 

Comparison  of  Old  and  New  Cereals. — The  old-fashioned  cereals 
were  much  more  economical.  Manufacturers  did  not  charge  for 
extra  manipulation.  They  were  bought  when  dry,  so  consumer 
was  not  paying  for  water  which  had  been  added  during  manu- 
facturing processes,  and  as  they  appeared  on  the  market  in  bulk 
the  box  was  not  included  in  the  weight. 

Uncooked  cereals  which  have  been  thoroughly  cooked  in  the 
home  digest  just  as  easily  as  predigested  kinds  and  are  equally 
nutritious.  In  these  respects  they  are  superior  to  some  varie- 
ties of  partly  cooked.  There  is  no  reason  to  believe  that  a  pre- 
pared food  is  more  favorable  to  health  than  cereal  itself  prop- 
er^ cooked. 

On  the  other  hand,  much  can  be  said  in  favor  of  the  use  of 
prepared  breakfast  foods  for  they  are  usually  palatable,  whole- 
some and  nutritious.  They  save  much  time,  labor  and  fuel  in 
the  home  and  are  well  suited  for  the  use  of  the  housekeeper,  who 
must  depend  upon  the  use  of  kerosene,  gas  or  electric  stove. 
From  a  sanitary  standpoint  there  has  been  a  great  improvement ; 
being  sold  in  cardboard  boxes  well  lined  with  air-tight  paper, 
they  are  protected  from  air,  moisture,  dust  and  micro-organism. 
Unless  carefully  packed  a  cereal  will  not  keep  well.  Moist  cli- 
mate makes  it  liable  to  be  attacked  by  mold  growth  and  it  is  apt 
to  become  infested  with  insects.  The  chief  point  against  the 
modern  cereal  is  the  excess  cost.  The  cost  of  cereal  per  pound 
is  2  to  3  cents;  cost  of  prepared  cereals  10  to  15  cents.  The 
cereals,  nevertheless,  pound  for  pound,  are  the  cheapest  com- 
plete food  that  can  be  found  on  the  market  and  they  form  a  legit- 
imate and  valuable  food. 

COFFEE  SUBSTITUTES. 

For  several  years  past  another  cereal  product  has  been  found 
on  the  market  known  under  the  name  of  coffee  substitutes. 
They  are  in  many  cases  put  up  by  the  same  manufacturers  as 
the  breakfast  foods  and  like  them  seem  to  be  gradually  increas- 


FOOD   INDUSTRIES  83 

ing  in  number.  They  are  as  a  rule  made  of  parched  grains  of 
wheat  and  barley  sometimes  mixed  with  wheat  middlings,  pea- 
hulls  and  molasses.  Some  of  the  first  products  also  contained  a 
low  grade  coffee  added  to  give  flavor.  Experiments  made  at  the 
Connecticut  Experiment  Station,  however,  show  that  the  present 
day  coffee  substitutes  are  .as  a  rule  made  from  the  cereal  grain 
as  claimed  by  the  manufacturers  and  that  there  is  now  very  little 
adulteration  of  this  kind. 

It  is  claimed  that  they  are  harmless,  unstimulating,  have  a 
flavor  resembling  coffee  and  yield  much  greater  nourishment  at 
lower  cost.  The  color  and  flavor  resembling  coffee  are  largely 
due  to  the  fact  that  the  carbohydrates  present  are  caramelized; 
this  also  occurs  in  the  roasting  of  coffee.  See  Chapter  XX,  Tea, 
Coffee  and  Coco.  Few  coffee  lovers  will  agree  that  the  flavor 
strongly  resembles  coffee  as  the  coffee  bean  also  contains  certain 
volatile  bodies  which  give  that  beverage  the  much  desired  aroma 
and  taste.  Substitute  coffee  where  coffee  has  not  been  added 
is  perfectly  harmless,  unstimulating,  and  furnishes  a  beverage 
for  those  who  cannot  take  coffee.  There  is  little  truth,  however, 
in  the  extravagent  claims  made  in  advertising  matter  as  to  the 
nutritive  value  of  the  beverage.  This  value  is  hardly  worth 
considering,  since  experiments  have  shown  that  skim  milk  is 
from  three  to  twenty  times  as  nutritious. 


CHAPTER  VII. 


UTILIZATION  OF  FLOUR.     BREADMAKING. 

By  far  the  oldest  and  most  important  product  made  from  flour 
is  bread.  The  art  of  breadmaking  dates  back  to  the  remotest 
ages  of  mankind  and  so  important  is  this  world's  food-stuff  that 
it  is  known  almost  universally  as  "The  staff  of  life."  With  the 
possible  exception  of  milk  and  eggs,  there  is  no  article  of  the 
diet  that  is  more  generally  used  by  human  beings  and  that  is  so 
well  able  to  sustain  life.  It  is  to  its  constant  use  that  we  owe 
the  wonderful  development  along  the  lines  of  the  cultivation  of 
wheat  and  the  equally  marked  progress  found  in  its  milling  oper- 
ations. 

In  a  broad  sense  bread  includes  all  forms  of  baked  flour, 
whether  leavened  or  unleavened,  but  our  common  use  of  the 
word  refers  only  to  those  forms  in  which  leavening  agents  are 
used,  other  products  being  spoken  of  as  pilot  bread,  crackers, 
passover  bread  and  biscuit.  Originally  all  bread  was  eaten  with- 
out leaven  for  the  savage  after  crushing  or  grinding  his  meal, 
baked  it  in  the  ashes  of  his  camp  fire.  The  result  was  a  bread 
of  hard,  tough  material  not  easy  for  the  digestive  fluids  to  act 
upon.  This  evidently  was  only  the  custom  among  the  most 
primitive  people,  for  the  use  of  leaven  is  very  ancient.  The 
Israelites  while  in  Egypt  used  leavened  bread,  the  Greeks  were 
known  to  have  cultivated  the  yeast  plant  and  in  the  ruins  of 
Pompeii  an  oven  was  found  containing  81  loaves  of  bread  not 
unlike  our  own.  With  the  use  of  leaven,  a  type  of  bread  was 
produced,  more  easily  masticated,  better  in  flavor  and  more 
easily  digested. 

Primitive  Breadmaking. — Crude  methods  of  breadmaking  can 
be  studied  not  only  by  the  earliest  historic  records  but  among 
some  of  the  more  primitive  nations  of  to-day.  Evidently  bread 
was  used  in  the  stone  age  for  burnt  specimens  have  been  re- 
covered among  the  Swiss  Lake  Dwellers ;  the  pyramids  of  Egypt 
bare  testimony  to  its  early  use  and  again  we  find  evidences  of  it 
in  the  mound  tombs  of  North  Africa  and  Asia.  The  method  of 


FOOD   INDUSTRIES  85 

preparation  was  undoubtedly  very  simple,  probably  much  like 
that  used  by  some  of  the  wild  tribes  that  inhabit  parts  of  Africa 
at  the  present  time.  It  is  their  custom  to  simply  grind  grain  be- 
tween two  stones,  make  it  into  a  paste  with  water,  then  bake  it  in 
the  ashes  of  a  camp  fire. 

In  different  parts  of  the  world  similar  products  can  be  found. 
Natives  of  some  of  the  West  Indies  prepare  a  thin  round  cake 
of  meal  which  is  obtained  from  the  cassava  root ;  it  is  known  as 
cassava  bread  and  furnishes  the  principal  food  among  the  com- 
mon people.  In  Mexico  and  Central  America,  a  bread  known  as 
"tortillas"  is  prepared  by  the  natives  from  Indian  corn  by  first 
parboiling  the  grain  to  soften  it,  then  crushing  it  by  means  of  a 
stone  rolling  pin.  The  paste  is  baked  on  a  plate  of  iron.  The 
"tortillas"  is  sold  at  many  of  the  market  places  by  native  women 
and  as  it  is  more  highly  relished  when  served  hot,  it  is  usually 
baked  on  a  small  portable,  charcoal  stove  at  the  market.  Among 
the  well-to-do  classes  of  India,  a  round,  flat,  cake  of  unleavened 
bread  called  "chapatties"  is  prepared  from  wheat  flour  and 
baked  on  a  griddle  or  on  the  coals.  A  similar  product  is  made 
by  the  poorer  classes  from  cornmeal,  millet,  barley  or  a  coarse, 
hard  grain  known  as  raggy.  In  Palestine  and  Syria  women  are 
still  the  millers  and  bakers,  grinding  the  meal  in  small  stone 
hand-mills  after  the  same  custom  as  was  used  long  before  the 
beginning  of  the  Christian  era.  The  coarse  meal  obtained  is 
made  into  flat  cakes  and  baked  on  a  hearth,  which  consists  of 
two  stones  raised  on  end  over  which  an  iron  plate  is  laid  to  hold 
the  bread.  Bread  made  in  other  parts  of  the  Orient  as  Egypt 
and  Turkey  has  quite  a  different  appearance.  Here  the  material 
is  rolled  or  pounded  into  a  flat  dough  similar  to  our  pie  crust; 
two  layers  are  then  put  together  united  at  the  edges  and  baked 
in  a  very  hot  oven.  The  expansion  of  the  air  between  these 
layers  puffs  up  the  dough  and  gives  the  appearance  of  a  large 
loaf.  A  flat  bread  of  coarse  barley  meal  is  also  made  in  the 
northern  part  of  Europe,  particularly  among  the  Norwegian 
peasants. 

The  evolution  from  these  primitive  breads  to  the  modern  white 


86  FOOD    INDUSTRIES 

loaf  used  by  the  civilized  world  has  needed  much  study  and  ex- 
perimentation as  in  the  development  of  all  other  industries. 
Probably  the  most  marked  change  was  the  use  of  leaven  and  it  is 
generally  supposed  that  it  is  to  the  Egyptians  that  the  world 
owes  this  important  step.  They  seemed  to  have  carried  the  art 
of  breadmaking  to  a  high  state  of  perfection,  as  did  also  the 
ancient  Greeks,  who  are  known  to  have  had  at  least  62  varieties 
of  bread.  From  the  days  of  these  ancient  civilizations,  mechan- 
ically there  seemed  to  be  little  progress  for  centuries  and  it  has 
been  left  to  the  modern  scientist  to  develop  the  art  and  science 
of  breadmaking. 

Leavened  Bread. — So  far  as  the  ingredients  are  concerned,  the 
present  day  bread  might  be  considered  a  very  simple  food,  for 
there  are  only  four  materials  needed  in  this  operation — flour, 
water,  yeast  and  salt.  Other  materials  as  butter,  lard,  sugar, 
milk,  fruit  or  spices  might  be  added  to  give  flavor  and  variety, 
but  they  are  not  essential  to  breadmaking.  Although  the  in- 
gredients are  so  simple,  scientists  tell  us  that  the  chemical 
changes  taking  place  in  the  preparation  of  the  loaf  are  very  pro- 
found. In  order  to  understand  at  least  a  small  part  of  these 
changes  it  is  necessary  to  consider  the  raw  material  to  be  used. 

Flour. — At  the  present  time  our  first-class  bakers  are  using  a 
standard  flour  for  breadmaking.  It  is  high  in  the  gluten  form- 
ing proteins  so  will  absorb  more  water  and  gives  a  larger,  lighter 
and  better  flavored  loaf.  For  milling  processes  see  Chapter  IV. 

Water. — The  hardness  or  softness  of  water  does  not  seem  to 
make  any  great  difference  in  breadmaking,  but  it  should  be  free 
from  dirt  or  contamination  of  any  kind.  See  Chapter  II,  Water. 
In  the  household  many  prefer  to  use  milk  in  part  or  altogether 
as  the  liquid.  It  makes  an  equally  light  loaf,  contains  a  larger 
amount  of  protein  and  fat,  is  equally  digestible,  but  the  dough  is 
slightly  longer  in  rising. 

Salt. — Salt  is  used  in  breadmaking  principally  for  the  flavor 
it  imparts,  for  without  it  the  dough  would  be  insipid.  The 
amount  varies  according  to  the  type  bread  and  in  different  locali- 
ties even  with  the  same  variety.  It  should  never  be  used,  how- 


FOOD    INDUSTRIES  87 

ever,  in  such  quantities  as  to  be  readily  tasted  or  the  delicate 
aroma  and  taste  of  the  bread  will  be  destroyed.  It  is  believed 
that  salt  added  in  small  quantity  stimulates  the  capacity  of  the 
palate  for  recognizing  flavors  of  other  substances.  This  accounts 
for  the  importance  of  salt  as  a  flavoring  agent. 

Another  reason  has  been  given  for  the  use  of  salt,  but  it  is 
not  now  believed  to  be  important.  It  has  the  power  of  control- 
ling some  of  the  chemical  changes  which  take  place  during  fer- 
mentation, so  was  considered  a  preservative.  It  checks  alcoholic 
fermentation  and  also  the  ropy  ferment,  but  it  does  not  influence 
the  lactic  acid  and  many  other  bacteria  from  working  so  its 
influence  as  a  preserving  agent  is  very  limited  and  can  hardly  be 
important  enough  to  be  considered. 

Yeast. — Yeast  was  the  first  leavening  agent  in  the  world's  his- 
tory and  is  still  by  far  the  most  important  one.  How  it  first 
came  to  be  used  is  not  told  us  in  history,  but  the  knowledge  that 
wild  yeast  is  always  present,  in  the  atmosphere  leaves  but  little 
to  the  imagination.  Its  use  might  easily  have  been  discovered 
by  accidentally  exposing  dough  to  the  atmosphere  and  after- 
wards finding  that  it  made  a  lighter  loaf.  From  this  simple 
custom  of  exposing  dough  to  the  air  we  might  easily  trace  the 
practice  of  saving  a  small  amount  of  raised  dough  from  day  to 
day  to  act  as  a  leavening  agent  for  the  next  baking.  Gradually 
the  art  of  cultivating  yeast  became  the  practice  among  the  civil- 
ized nations. 

Although  yeast  has  been  used  as  a  leavening  agent  for  many 
centuries  very  little  was  really  known  about  it  until  the  time  of 
Pasteur.  It  is  now  believed  that  yeast,  molds  and  bacteria 
belong  to  a  class  of  substances  known  as  ferments.  Until 
quite  recently  these  ferments  were  divided  into  two  classes : 
ist,  enzymes,  such  as  diastase  and  ptyalin  or  unorganized  fer- 
ments; 2nd  yeast,  molds  and  bacteria,  known  as  organized  fer- 
ments. Recent  research  has  revealed  that  micro-organisms  can- 
not do  their  work  as  ferments  without  the  presence  of  enzymes 
within  their  cell-walls  so  that  classification  no  longer  can  be  used. 
Yeast,  molds  and  bacteria  are  now  known  to  be  living  organisms. 
7 


88  FOOD    INDUSTRIES 

They  are  microscopic  forms  of  plant  life  which  in  their  desire 
for  food  can  act  upon  substances,  bringing  about  many  profound 
changes.  Although  the  nature  of  these  changes  may  not  be 
known  to  the  average  house-wife,  with  the  effects  of  many  she 
is  quite  familiar.  Milk  after  standing  for  a  time,  particularly 
in  a  warm  place  changes  in  its  nature ;  it  develops  acid  qualities 
and  is  spoken  of  as  being  sour.  Butter  under  certain  conditions 
becomes  rancid.  Cider  when  fresh  has  a  decidedly  sweet  taste 
which  in  time  gradually  disappears  and  is  replaced  by  an  unmis- 
takable taste  of  alcohol.  It  is  quite  common  to  speak  of  this 
product  as  hard  cider  and  every  house-keeper  knows  that  should 
hard  cider  be  kept  long  enough  it  will  change  to  vinegar.  These 
changes  and  many  others  modern  scientists  have  traced  to  the 
fermentative  actions  of  micro-organisms. 

In  the  fermentation  brought  about  by  the  yeast  plant  two  very 
important  products  are  found,  alcohol  and  carbon  dioxide,  which 
are  used  throughout  the  world  whether  the  races  are  civilized  or 
still  in  a  semi-barbarous  condition.  Alcohol  is  particularly  de- 
sired by  all  industries  preparing  stimulating  beverages  and  car- 
bon dioxide  is  needed  for  the  lightening  of  bread.  It  is  to  the 
manufacturer  of  alcoholic  beverages  that  we  owe  the  scientific 
study  that  has  been  given  to  the  yeast  plant. 

When  viewed  through  a  microscope  yeast  is  found  to  consist 
of  a  single  cell  round  or  oval  in  shape.  It  is  perfectly  colorless, 
belonging  to  a  class  of  plants  without  chlorophyll — the  fungi. 
Each  cell  is  an  individual  plant  consisting  of  an  outer  wall  of 
cellulose  filled  with  protoplasm.  In  this  condition  yeast  is  usually 
spoken  of  as  in  the  resting  state. 

Being  a  living  organism  yeast  is  capable  of  reproducing  itself 
should  conditions  be  favorable.  The  normal  reproduction  is 
through  a  process  of  budding.  If  a  little  of  this  resting  yeast  is 
put  under  conditions  favorable  for  growth,  a  daughter  cell  or 
bud  is  formed  within  the  cell.  The  bud  pushing  its  way  through 
the  wall  rapidly  develops,  separates  from  the  parent  cell,  and  in 
its  turn  is  able  to  become  a  parent  cell.  When  growth  is  very 
rapid  the  cells  sometimes  fail  to  separate,  and  adhering,  form  a 


FOOD   INDUSTRIES  89 

chain  of  cells  which  can  easily  be  seen  in  the  microscope.  Pas- 
teur states  that  on  one  occasion  he  watched  two  cells  for  two 
hours;  during  that  time  they  multiplied  into  eight. 

Under  unfavorable  conditions  some  yeasts  are  reproduced  by 
the  formation  of  spores.  These  spores  can  resist  many  adverse 
circumstances,  such  as  lack  of  moisture,  insufficient  food  and 
marked  changes  in  temperature.  It  is  to  their  hardy  nature  that 
we  owe  the  constant  presence  of  yeast  in  the  atmosphere.  In 
this  state  it  has  been  discovered  yeast  can  live  in  the  ground  for 
some  little  time,  until  wind  carrying  them  into  the  air,  gives  an 
opportunity  for  settling  amid  favorable  surroundings  and  again 
•growth  and  reproduction  take  place.  The  favorite  home  for  the 
yeast  plant  is  on  the  skin  of  grapes  and  other  fruit,  a  fact  well 
appreciated  by  those  engaged  in  the  wine  industry. 

The  rapidity  of  the  growth  is  much  influenced  by  surrounding 
the  yeast  with  favorable  conditions  of  temperature,  suitable  food, 
oxygen  and  moisture. 

The  temperature  found  to  be  most  favorable  is  77° -95°  F. 
Below  77°  F.  the  growth  is  slower  and  a  little  below  49°  F.  it  is 
practically  arrested.  The  vitality  of  the  cell  is  not  destroyed  by 
a  low  temperature  for  even  after  exposure  to  32°  F.  yeast  will 
grow  if  the  conditions  are  once  more  favorable.  Above  95°  F. 
yeast  will  become  gradually  weakened  by  heat  until  it  is  finally 
killed  at  a  temperature  of  140°  F.  if  the  yeast  is  moist.  Dry  yeast 
can  stand  a  much  higher  temperature,  200°  F.,  without  destroying 
life.  Although  yeast  grows  most  rapidly  between  77°-95°  F. 
it  is  sometimes  advisable  to  keep  the  temperature  lower  to  pre- 
vent the  action  of  undesirable  micro-organisms.  Brewers  in  the 
United  States  and  on  the  continent  are  now  using  a  lower  tem- 
perature although  none  but  the  largest  and  more  scientific  bakers 
seldom,  if  ever,  take  advantage  of  this  fact. 

Food  for  yeast  growth  must  contain  carbohydrate,  nitrogenous 

compounds    and    appropriate    inorganic    matter.     The    last    two 

food  principles   are  necessary   for  the   healthy   development   of 

yeast  for  they  constitute  as  in  human  life,  the  building  material 

'of  the  cells. 


9O  FOOD    INDUSTRIES 

Pasteur  discovered  that  unless  these  substances  are  given  to 
yeast  they  act  like  cannibals,  the  stronger  cells  existing  on  the 
weaker.  From  our  standpoint  the  carbohydrate  is  the  most  im- 
portant food  for  the  yeast  as  it  is  to  these  compounds  that  we 
look  for  the  production  of  alcohol  and  carbon-dioxide.  All 
forms  of  carbohydrate  cannot  be  utilized  by  yeast  but  should  the 
compound  not  be  available  as  food,  yeast  carries  its  own  enzyme, 
much  as  we  do,  which  can  convert  it  into  a  form  which  can  be 
utilized.  There  are  two  important  enzymes  in  yeast — invertase 
and  zymase.  The  function  of  invertase  is  to  convert  such  com- 
pounds as  starch  and  dextrin  into  glucose  by  the  process  of 
hydrolysis : 

(C.H..O,).  -I-  H20  ~  C.H,,0.. 

Glucose  being  an  available  food  for  yeast  it  is  attacked  by 
zymase  which  breaks  down  the  sugar  into  alcohol,  carbon  dioxide 
and  a  number  of  other  substances  in  small  quantities  such  as 
fusel  oils,  succinic  acid  and  glycerine. 

C6H1206  ~  2C,H6OH  +  2C02. 

Micro-organisms  also  need  oxygen,  some  taking  it  in  the  form 
of  atmospheric  oxygen  O2  and  others  from  their  food.  Yeast 
needs  atmospheric  oxygen.  Pasteur  discovered  that  an  abund- 
ance of  air  caused  the  plant  to  develop  rapidly,  but  the  evolu- 
tion of  alcohol  and  carbon  dioxide  was  very  slow,  while  in  a 
limited  amount  of  oxygen  fermentation  proceeded  rapidly  and 
the  cell  growth  was  arrested.  This  idea  has  been  of  great  bene- 
fit to  brewers  and  to  scientific  bread  bakers  who  now  know  when 
to  limit  the  supply  of  oxygen. 

Yeast  needs  also  for  development  a  certain  amount  of  moist- 
ure. In  fact  one  of  the  largest  and  best  known  breadmaking 
concerns  in  the  United  States  make  their  bread  .under  a  process 
patent,  based  on  the  idea  of  mixing  the  dough  in  such  a  manner 
as  to  inject  into  the  dough  an  unusual  amount  of  atmospheric 
oxygen. 

Leavening  Effect  of  Yeast. — With  these  facts  in  mind  the 
leavening  effect  of  yeast  can  easily  be  seen.  A  mixture  of  flour 
and  water  readily  supplies  the  moisture  and  food,  flour  con- 


FOOD    INDUSTRIES  9 1 

taining  all  the  necessary  compounds — carbohydrate,  protein  and 
mineral  matter.  If  this  material  be  kept  exposed  to  the  atmos- 
phere and  at  a  suitable  temperature,  yeast  will  multiply  very  rap- 
idly and  will  spread  throughout  the  dough.  As  a  result  of  its 
action  much  carbon  dioxide  is  developed,  which  in  forcing  its 
way  through  the  dough  becomes  entangled  in  the  gluten.  The 
latter  being  elastic  stretches,  thus  giving  porosity  and  lightness 
to  the  dough. 

Yeast  Preparations — Breadmaking. — The  oldest  method  of  pre- 
paring yeast  was  very  probably  that  used  by  the  ancient  Egypt- 
ians, who  succeeded  in  obtaining  wild  yeast  and  growing  it  in 
dough.  A  portion  of  this  dough  or  "leaven"  was  always  saved  for 
the  next  baking  and  as  it  contained  yeast  cells,  again  yeast  could 
be  grown  when  needed.  This  simple  custom  has  been  used  more 
or  less  from  those  early  days  to  modern  times  and  in  some  parts 
of  the  world  it  is  still  practiced.  The  home  brew  used  by  our 
ancestors  and  which  can  still  be  found  in  isolated  districts  is  a 
preparation  of  this  kind.  The  leaven  saved  from  the  last  baking 
is  mixed  with  suitable  material  for  the  rapid  growth  of  yeast. 
A  decoction  of  hops  or  potatoes  and  water  were  used  and  when 
the  yeast  had  developed,  part  of  this  material  was  added  to  the 
dough.  A  similar  practice  can  be  found  in  Scotland  at  the 
present  time.  The  "barm"  as  it  is  called  is  prepared  by  allow- 
ing yeast  to  grow  in  malt  extract  and  flour  before  adding  it  to  the 
bread  dough.  In  some  parts  of  the  continent  this  ancient  method 
is  still  used  by  bakers  and  in  many  places  by  the  poor  country 
people,  particularly  in  France  and  Switzerland.  The  bread  has 
a  sour  taste  due  to  the  development  of  lactic  and  butyric  acid 
bacteria,  which  is  relished  by  many  people.  Some  authorities 
consider  bread  made  in  this  way  more  healthful  as  the  acids 
developed  are  supposed  to  assist  in  digestion.  The  taste,  how- 
ever, is  disagreeable  to  the  majority  of  people  and  the  best  au- 
thorities of  our  country  consider  that  a  high  grade  commercial 
yeast  is  more  reliable  and  much  more  convenient. 

Breiver's  Yeast. — One  of  the  earliest  commercial  yeasts  was 
obtained  from  brewers.  During  the  fermentation  of  beer,  es- 


92  FOOD    INDUSTRIES 

pecially  where  a  high  temperature  is  used,  much  of  the  yeast  is 
carried  to  the  top  of  the  vats  by  the  escaping  carbon  dioxide. 
It  is  called  by  the  brewer  top  yeast.  This  yeast  was  skimmed 
from  the  top  of  beer  and  was  sold  in  the  liquid  form.  Little 
care  was  given  to  sanitary  conditions  and  the  product  was  thor- 
oughly unreliable.  It  was  dark  in  color  and  carried  with  it  the 
flavor  and  aroma  of  the  hops.  Bread  made  from  it  was  some- 
what smaller  in  volume,  due  to  slow  fermentation,  dark  in  color 
and  had  a  faintly  bitter  flavor.  It  has  now  almost  entirely  been 
superseded  by  distillers'  yeast,  which  at  the  present  time  is  sold  in 
the  form  of  the  compressed  yeast  cake. 

Compressed  Yeast  Cake. — Distiller's  yeast  is  lighter  in  color 
and  possesses  a  rather  pleasant  taste.  At  the  time  that  fer- 
mentation is  most  energetic  the  yeast  is  skimmed  off  the  surface 
and  is  conveyed  by  wooden  drains  to  sieves.  All  foreign  matter 
is  removed  and  the  strained  liquid  passes  on  to  the  settling  cis- 
terns. Here  the  yeast  settles  and  the  liquid  is  drawn  off.  The 
yeast  is  generally  mixed  with  starch  and  put  into  presses  which 
squeeze  out  much  of  the  moisture,  leaving  a  dough-like  paste. 
The  starch  is  said  to  be  added  because  it  permits  more  water 
being  removed,  which  greatly  aids  the  keeping  quality.  In  recent 
years,  however,  the  foremost  yeast  manufacturers  of  our  country 
have  discovered  that  by  strict  laboratory  control  and  the  develop- 
ment of  pure  culture,  compressed  yeast  of  great  strength  and  uni- 
form quality  and  flavor  can  be  successfully  and  commercially 
made  without  the  addition  of  starch.  The  latter,  in  fact,  is  now 
looked  upon  as  an  adulterant.  Yeast  is  then  partly  dried,  made 
into  cakes,  and  carefully  wrapped  in  metal  or  waxed  paper  to 
protect  it  from  bacteria.  This  is  the  best  all-around  yeast  that  is 
used  at  the  present  time.  It  is  more  expensive,  but  will  work 
evenly  and  quickly  and  will  give  a  finished  loaf  of  bread  with  a 
good  volume  and  texture  and  having  an  agreeable  taste,  odor  and 
color.  A  good  quality  should  be  slightly  moist,  possess  a  creamy 
white  color  and  should  break  with  a  fine  fracture. 

Dried  Yeast. — There  is  one  great  disadvantage  to  compressed 
yeast;  even  under  favorable  conditions  it  will  only  keep  fresh 


FOOD    INDUSTRIES  93 

for  a  comparatively  short  time.  The  yeast  begins  to  die  and  other 
forms  of  micro-organisms  begin  to  develop,  giving  rise  to  unde- 
sirable flavors  in  bread.  For  people  who  live  in  isolated  dis- 
tricts, another  type  of  compressed  yeast  called  dried  yeast  is  put 
on  the  market.  More  starch  has  been  added  and  more  water 
removed.  Although  a  low  temperature  is  used  to  dry  the  yeast 
some  of  the  cells  are  undoubtedly  killed,  so  it  is  not  as  satisfac- 
tory a  form  to  use  as  a  fresh  yeast.  On  account  of  the  dryness, 
however,  decomposition  cannot  set  in  and  some  of  the  yeast  and 
spores  will  remain  alive  for  a  considerable  length  of  time,  and 
when  mixed  with  water  and  a  soluble  carbohydrate  will  slowly 
begin  to  grow. 

Object  in  Breadmaking. — Given  the  necessary  ingredients,  it  is 
the  baker's  object  to  produce  a  result  which  will  be  pleasing  to 
the  sight,  agreeable  to  the  taste,  easy  of  digestion  and  nutritious. 

Steps  in  Breadmaking. — i.  FERMENTATION. — The  methods  of 
fermenting  dough  are  somewhat  varied,  but  there  are  only  three 
in  common  use : 

I.  Straight  or  off-hand  dough. 
II.  Ferment  and  dough. 

III.  Sponge  and  dough. 

No  matter  which  method  is  chosen  the  best  material  possible 
lo  procure  should  be  used;  the  ingredients  should  be  thoroughly 
mixed  and  in  proper  proportions,  and  the  greatest  cleanliness 
should  be  observed  throughout  the  entire  operation. 

I.  Straight  or  Off-hand  Dough. — With  this  method  all  of  the 
ingredients  while  luke-warm  are  thoroughly  mixed.  Care  should 
be  taken  that  the  proper  proportions  are  used ;  too  little  yeast  will 
give  a  badly  raised  dough  and  too  much  will  cause  excessive  gas 
which  stretches  the  gluten  beyond  its  limit,  causes  it  to  break  open 
and  the  gas  to  escape,  thus  making  a  heavy,  soggy  loaf  of  bread. 
The  dough  is  then  set  aside  to  rise  in  a  moderately  warm  tem- 
perature (77°-95°  F.).  It  should  be  kept  as  free  from  drafts 
as  possible  and  should  be  left  exposed  to  the  atmosphere  or 
lightly  covered,  as  the  presence  of  oxygen  aids  the  growth  of 
yeast.  As  fermentation  proceeds  the  dough  increases  in  bulk  and 


94  FOOD    INDUSTRIES 

becomes  light  and  porous.  When  sufficiently  aerated  with  gas 
it  is  thoroughly  kneaded  by  hand  or  machinery.  This  operation 
causes  the  escape  of  waste  gases,  incorporates  fresh  air,  revives 
the  activity  of  the  yeast,  has  a  toughening  effect  on  the  gluten 
and  assists  its  elasticity.  The  dough  is  shaped  into  loaves, 
allowed  to  ferment  again  and  then  baked.  Bread  made  in  this 
way  takes  from  3  to  10  hours  according  to  the  amount  of  yeast 
and  the  temperature  used.  There  are  several  distinct  advantages 
to  this  method — all  labor  of  sponging  and  extra  manipulation  is 
saved  and  bread  is  produced  in  less  time.  It  is  far  more  con- 
venient when  bread  is  made  at  home. 

II.  Ferment  and  Dough. — Among  many  bakers  the  first  step 
is  the  preparation  of  the  ferment;  that  is,  the  cultivation  of  the 
yeast  by  giving  it  appropriate  food.     Potato  mash  is  still  largely 
employed  for  food,  also  raw  and  scalded  flour,  malt  extract  and 
commercial  yeast  foods.     The  ferment  takes  about  5  hours,  but 
is  still  used  by  bakers  for  two  reasons :   first,  it  enables  an  origin- 
ally small  amount  of  yeast  to  do  much  work ;  second,  the  young 
yeast  cells  are  very  vigorous.     This  yeast  is  then  incorporated 
with  water,  flour  and  salt  and  a  dough  is  made  similar  to  the 
straight-dough  method. 

III.  The   Sponge   and  Dough   Method. — In   this   process   the 
dough  is  made  in  two  stages  by  allowing  the  yeast  to  work  for  a 
period  in  a  portion  of  the  flour  and  water.     Several  different 
sponges  are  used — the  quarter,  the  third,  the  half  and  the  three- 
quarter,  according  to  the  amount  of  flour  added.     Fermentation 
proceeds  from  2  to  12  hours  and  the  remaining  material  is  incor- 
porated.    Care  should  be  given  to  mix  the  second  portion  of 
flour  thoroughly  with  the  sponge  or  the  bread  will  contain  lumps 
on  which  the  yeast  has  had  no  opportunity  to  work.    The  dough 
as  it  is  now  called  is  allowed  to  rise  again,  is  kneaded  into  loaves 
and  baked.    Although  it  takes  longer  and  requires  more  manipu- 
lation the  sponge  method  has  many  advantages :   first,  on  account 
of  its  slackness,  it  requires  much  less  yeast — this  is  a  considerable 
saving  where  bread  is  made  in  large  quantities;   second,   hard 
wheat  flour  on  account  of  its  absorbing  power  does  not  produce 


FOOD    INDUSTRIES  95 

a  desirable  loaf  of  bread  when  made  by  the  off-hand  method — a 
sponge  gives  a  lighter  and  more  elastic  loaf ;  third,  bread  made 
with  a  sponge  is  usually  finer  in  texture  and  has  a  better  flavor; 
fourth,  it  keeps  better;  fifth,  some  believe  that  less  work  is 
involved  in  mixing  as  the  sponge  softens  on  standing. 

2.  BAKING. — The  dough  should  be  evenly  baked  in  an  oven 
ranging  from  450°  to  550°  F.  according  to  the  variety  of  bread. 
The  heat  should  not  be  too  great  at  first  or  the  bread  will  harden 
too  quickly.     The  gas  in  the  interior  will  not  have  a  chance  to 
expand  the  gluten  and  the  result  will  be  a  heavy  bread.     In  some 
bakeries  the  temperature  is  gradually  raised  during  baking.    The 
effect  of  this  heat  is  to  rapidly  expand  the  gas  which  in  its  turn 
expands  the  gluten  and  swells  the  loaf.     As  gluten  is  protein  in 
nature  it  very  shortly  coagulates  and  thus  holds  the  loaf  in  shape 
after  the  escape  of  the  gases.    The  surplus  moisture,  the  alcohol 
and  acids  volatilize.     In  time  the  starch  granules  are  ruptured 
and  become  suitable  for  human  food.     On  the  outer  portion  or 
crust  on  account  of  the  intense  heat,  most  of  the  starch  is  dex- 
trinized  and  a  small  portion  is  converted  into  glucose.    The  inner 
part  or  crumb  is  not  subjected  to  as  intense  heat,  since  dough  is 
not  a  good  conductor  of  heat.     The  interior  is  not  heated  above 
the  boiling  point  of  water  so  the  changes  in  the  carbohydrate 
grow  less  as  it  approaches  the  center  of  the  loaf.    The  yeast  and 
bacteria  are  killed  during  baking  and  all  enzymes  present  in  the 
yeast  and  flour.    This  sterilizes  the  bread. 

3.  COOLING. — As  soon  as  completely  baked,  bread  should  be 
placed   on   sieves  or  bread-racks   so  that  the  air   can   circulate 
around  them  until  they  are  thoroughly  cool.     This  gives  the  gas 
and  steam  within  the  loaves  an  opportunity  to  escape  and  pre- 
vents the  bread  from  becoming  damp. 

A  Modern  Bread  Factory. — In  strong  contrast  to  the  old- 
fashioned  cellar  bakery  with  its  dingy  and  many  times  insanitary 
surroundings,  the  modern  bread  factory  has  arisen.  Here  can 
be  found  bread  being  manufactured  on  a  large  scale  in  a  well 
ventilated,  sun-lighted  building  equipped  with  facilities  as  nearly 
perfect  as  modern  science  can  suggest.  An  electric  plant  for 


96 


FOOD    INDUSTRIES 


lighting  the  building  and  running  the  machinery,  a  cold  storage 
plant  and  hot  water  system  for  regulating  temperature,  elevators, 
conveyors  and  slides  for  carrying  material  from  one  part  of  the 
building  to  another,  can  be  seen.  Many  curious  devices  in 
machinery  have  been  invented,  so  that  the  human  hand  needs 
scarcely  to  touch  the  product  from  the  time  that  the  raw  materials 
enter  the  building  until  the  finished  loaf  is  ready  to  be  carried 


Fig.  18.— Flour  Sifter  and  Blender. 
(Courtesy  of  Ward  Baking  Co.) 

out  for  delivery.  Conditions  insuring  thorough  cleanliness  are 
carefully  sought  and  the  bread  is  made  amid  thoroughly  sanitary 
surroundings.  Only  a  high  grade  flour,  good  yeast,  distilled 
water  and  the  best  available  material  for  shortening  are  used. 
Before  being  utilized  the  flour  is  passed  through  a  sieve  con- 
taining rotary  brushes  and  a  surprising  amount  of  wood,  lint, 
dust  and  other  foreign  material  are  removed.  When  needed. 


FOOD    INDUSTRIES 


97 


the  sifted  flour  passes  automatically  to  electric  bread  mixers,  as 
does  also  the  required  amount  of  water,  dissolved  yeast,  salt,  etc. 
As  the  bread  mixer  revolves,  filtered  air  is  fed  to  the  dough  in 
order  to  hasten  the  action  of  the  yeast  and  give  whiteness  to  the 
product.  The  mixing  operation  requires  some  25  minutes.  The 
mixer  is  then  turned  over  and  the  dough  drops  into  the  raising 
trough,  where  it  is  allowed  to  rise  in  a  sunny,  white-tiled  room 


Fig.  19. — Mixing  Machine  with  Dough  About  to  be  Lowered  Into  Raising  Trough. 
(Courtesy  of  Ward  Baking  Co.) 

for  3  hours.  As  soon  as  the  dough  is  in  proper  condition,  the 
bottom  of  the  tub  is  removed  and  the  dough  proceeds  by  gravity 
through  an  opening  in  the  floor  to  an  apartment  below,  where  it  is 
automatically  carried  to  a  machine  which  weighs  and  cuts  it  into 
uniform  pieces.  It  passes  on  a  moving  platform  in  separate 
loaves  to  a  number  of  kneading  devices  which  roll  and  press  it 
into  shape.  The  loaf  travels  forward  and  backward  on  a  con- 


FOOD    INDUSTRIES 


veyor,  where  it  is  allowed  to  rest  before  it  drops  into  a  pan  ready 
for  the  second  rising.  The  pans  are  removed  to  an  apartment 
heated  to  110°  F.,  and  the  bread  is  allowed  to  rise.  It  is  then 
baked  at  a  temperature  of  450-550°  F.  On  being  removed  from 
the  oven,  the  bread  falls  on  racks  from  which  place  it  proceeds 
on  an  incline  to  the  floor  belowr  where  after  cooling,  it  is  wrapped 
and  sealed  in  paraffin  paper. 


Fig.  20. — Machine  for  Dividing  Dough  Into  Equal  Parts  of  Equal  Weight. 
(Courtesy  of  Ward  Baking  Co.) 

Souring  and  Its  Prevention. — The  souring  of  bread  is  due  to 
the  development  of  lactic  and  butyric  acid  ferments.  This  may 
be  caused  by  a  poor  grade  of  yeast  which  is  apt  to  contain  un- 
desirable bacteria;  by  a  poor  flour  which  on  account  of  the 
presence  of  certain  nitrogenous  bodies  gives  a  medium  particu- 
larly suitable  for  bacterial  growth ;  by  dirty  vessels ;  by  allowing 
the  sponge  to  proceed  too  far  thus  giving  the  acetic  ferment  an 


FOOD    INDUSTRIES 


99 


opportunity  to  develop.  It  may  be  prevented  by  using  a  high 
grade  flour,  a  good  yeast  and  by  thorough  cleanliness:  Too  high 
a  temperature  during  fermentation  and  prolonged  raising  of  the 
sponge  and  dough  should  be  avoided.  Sudden  changes  in  tem- 
perature should  be  guarded  against. 

Adulteration  of  Bread. — Alum  has  been  largely  used  and  evi- 
dently for  a  long  period.     English  history  speaks  of  Henry  VIII 


Fig.  21  — Front  View  of  Dough  Divider. 
(Courtesy  of  Ward  Baking  Co.) 

ordering  his  baker  to  be  hanged  for  using  alum  in  bread  intended 
for  the  King's  table.  This  subject  has  been  much  discussed  of 
late  years  and  its  use  has  been  finally  prohibited  by  the  Pure 
Food  Law.  As  a  rule  alum  was  used  with  a  poor  grade  flour 
or  with  a  flour  that  had  been  kept  for  a  long  time  under  unfa- 
vorable conditions.  When  flour  deteriorates  the  protein  some- 
times changes,  becoming  more  soluble  and  will  not  make  a  good 


IOO  FOOD    INDUSTRIES 

dough.  Alum  will  cause  it  once  more  to  become  insoluble  and  a 
better  gluten  will  be  formed.  The  loaf  is  larger,  less  sodden, 
whiter  and  gives  the  appearance  of  a  better  grade  flour. 

Losses  in  Fermentation. — In  the  preparation  of  bread  by  means 
of  yeast,  appreciable  losses  of  dry  material  must  necessarily  take 
place.  This  is  caused  by  the  formation  of  volatile  matter  during 
fermentation,  such  as  carbon  dioxide,  alcohol  and  acids.  Thev 


•    Fig.  22. — Machine  for  Wrapping  Bread  with  Paraffin  Paper. 
(Courtesy  of  Ward  Baking  Co.) 

are  driven  off,  to  a  large  extent,  at  the  temperature  of  baking, 
so  have  no  nutritive  effect.  Estimates  of  this  loss  have  been 
taken  and  as  a  rule  it  has  been  found  to  be  approximately  2  per 
cent,  although  it  may  be  much  higher  under  unfavorable  con- 
ditions. Liebig  calculated  that  the  loss  in  Germany  daily  would 
supply  400,000  persons  with  bread  and  it  has  been  estimated  that 
300,000  gallons  of  alcohol  are  annually  wasted  in  the  bakers' 


FOOD    INDUSTRIES 


101 


ovens  in  London.  There  has  been  much  experirnen,(jng  ^nxl-- large, 
sums  of  money  expended  in  trying  to  recover 'this' alcohol,  bat 
without  success  from  the  baker's  standpoint ;  the  bread  was 
found  to  be  dry  and  unpalatable.  This  inevitable  waste  has  led 
to  attempts  to  convert  dough  into  a  porous  form  by  other  methods 
than  that  of  fermentation.  Many  mechanical  and  chemical  proc- 
esses of  aerating  dough  with  CO2  have  been  invented,  but  in 


Fig.  23.— Bread  After  Leaving  Wrapping  Machine. 
(Courtesy  of  Ward  Baking  Co.) 


England  and  the  United  States,  only  two  have  met  a  slight  suc- 
cess. 

I.  Chemical  Process. — Use  of  baking  powders.     See  Chapter 
VIII. 

II.  Aerated  Bread. — In  this  process  water  is  saturated  with 
CO2  prepared  by  chemical  reaction.     This  highly  charged  water 
is  then  mixed  with  flour  under  pressure  in  air-tight  chambers. 


IO2  FOOD    INDUSTRIES 

When  the  pressure  is  lowered  the  dough  is  forced  out  and  blown 
up  by  the  expanding  gas.  It  is  cut  into  loaves  quickly  and  baked. 
This  bread  is  very  light,  porous  and  involves  no  waste  of  ma- 
terial but  unfortunately  it  has  an  insipid  taste  due  to  the  absence 
of  the  by-products  of  yeast,  so  has  never  met  with  great  success. 

THE  CRACKER  OR  BISCUIT  INDUSTRY. 

Those  products  formerly  known  in  the  United  States  as  crack- 
ers and  in  England  as  biscuit  originally  included  only  varieties 
of  unleavened  bread,  such  as  the  commonly  known  pilot  bread, 
ship's  biscuits  and  water  crackers,  but  the  march  of  progress 
in  the  last  half  century  has  greatly  enlarged  the  field  of  this 
industry  until  it  now  includes  many  articles  formerly  considered 
cakes,  pastry  and  confectionery. 

In  both  this  country  and  in  England  the  manufacture  of  bis- 
cuit has  been  greatly  improved  and  the  output  tremendously  in- 
creased, one  American  firm  alone  manufacturing  some  four  hun- 
dred or  more  different  varieties.  Great  manufacturing  concerns 
have  been  attracted  by  this  field  of  business  and  have  by  their 
efforts  to  produce  a  perfect  product  brought  about  improvements 
resulting  in  cleanliness  and  sanitation  in  the  manufacture  of  these 
products.  The  dirty  and  insanitary  cracker  bin  and  barrel  of  the 
grocery  store,  s'uch  as  was  fomerly  used  when  crackers  and  bis- 
cuit were  sold  only  in  bulk  form,  the  chance  for  the  small  dealer 
to  deceive,  the  many  varieties  of  cheap  scales,  and  such  numerous 
handlings  as  were  necessary  to  deliver  the  goods  to  the  purchaser 
are  all  things  of  the  past.  The  public  now  receives  its  biscuit 
in  air-tight,  moisture  and  dust-proof  packages,  packed  and  sold 
under  the  best  possible  conditions  and  free  from  the  touch  of 
human  hands  on  their  journey  from  the  factory  to  the  table  of  the 
consumer. 

Raw  Material. — For  the  most  part,  flour  made  from  winter 
wheat  is  used  in  the  preparation  of  biscuit,  although  different 
varieties  will  contain  Graham,  whole  wheat  and  cereal  flours. 
Butter,  lard  and  specially  prepared,  refined  fats  from  vegetable 
sources  shorten  the  goods,  and  pure  water  or  high  grade  milk 
furnishes  the  moisture,  while  yeast,  bi-carbonate  of  soda,  baking 


FOOD    INDUSTRIES 


103 


powder  or  aeration,  assisted  by  the  presence  of  eggs  and  fatty 
matter,  serves  as  a  leavening  agent.  There  are  many  varieties  of 
fancy  biscuit  in  which  are  used  refined  sugar,  fruits,  spices, 
cheese,  eggs,  chocolate,  nuts  and  confectionery.  The  ingredients, 
as  above  set  forth,  are  carefully  measured  and  weighed,  then 
placed  in  a  mixer,  usually  a  large  steel  receptacle  with  revolving 
arms,  and  are  thoroughly  mixed  by  machinery  for  a  definite 
time.  If  the  leavening  agent  be  yeast,  a  period  of  incubation  at 
a  properly  fixed  temperature  must  follow.  The  dough,  now 


Fig.  24.— A  Baking  Floor  showing  Ovens.     (Courtesy  of  The  National  Biscuit  Co.) 

thoroughly  mixed  and  having  been  allowed  to  rise  the  proper 
length  of  time,  is  wheeled  in  its  clean  steel  car  to  the  dough- 
breaks  where,  by  being  rolled  and  folded  between  great  rollers,  it 
is  kneaded  into  the  proper  thinness  and  ready  for  the  machine 
which  further  shapes  and  stamps  it  into  the  form  in  which  it  is 
baked  with  the  design  and  trade  mark  impressed  on  the  dough. 
The  ovens  used  to  bake  biscuit  are  generally  direct  heat  with 


IO4  FOOD    INDUSTRIES       / 

rotating  shelves  and  are  kept  at  a  temperature  approximating 
500°  F.  After  being  baked  and  taken  from  the  oven,  the  biscuits 
are  cooled  and  immediately  packed  in  their  moisture  and  dust- 
proof  packages,  in  which  they  start  their  journey,  often  the 
same  day  they  are  packed,  to  the  ultimate  consumer  (Fig.  24). 

MACARONI. 

In  the  world's  food  products  made  from  wheat,  macaroni  has 
occupied  an  important  place  in  the  diet  of  several  nations.  The 
Japanese  claim  to  be  the  original  manufacturers  but  whether  this 
be  true  or  not,  the  Europeans  first  heard  of  it  from  the  Chinese 
who  had  been  using  it  for  a  long  period.  Although  the  Germans 
were  the  European  discoverers  of  macaroni,  it  was  the  Italians 
who  early  learned  to  appreciate  its  virtues  and  to  adopt  it  as  a 
national  food.  By  the  I4th  century,  Italy  was  the  only  European 
nation  that  understood  its  preparation,  and  for  nearly  four  hun- 
dred years  she  held  the  secret  of  the  method  of  manufacture. 

The  Italian  macaroni  industry  had  its  birth  in  Naples  from 
whence  it  spread  throughout  Italy  and  finally  to  other  parts  of 
Europe,  but  it  was  not  until  the  latter  part  of  the  igth  century 
that  this  product  could  be  equaled  in  any  other  country.  It  was 
finally  introduced  into  France  where  it  has  become  an  important 
industry.  Although  the  United  States  is  still  a  large  importer  of 
macaroni,  there  has  been  a  great  growth  in  the  macaroni  industry 
since  the  cultivation  of  durum  wheat  in  our  own  northwestern 
states. 

In  the  preparation  of  macaroni  a  hard,  very  glutenous  wheat 
is  used,  called  macaroni  wheat.  The  early  Neapolitan  manufac- 
turers won  their  fame  on  account  of  the  excellent  quality  of  the 
Italian  wheat.  Unfortunately  the  cultivation  of  native  wheat 
is  now  sadly  neglected  in  Italy.  Russia  for  a  long  period  has 
produced  some  of  the  finest  varieties.  They  were  grown  exten- 
sively for  macaroni-making  long  before  Liebig  started  his  experi- 
mentation on  hard  wheat  as  a  breadmaking  material.  Algerian 
durum  wheat,  the  wild  goose  wheat  of  Canada  and  Argentina 
macaroni  wheat  are  also  largely  exported  for  this  industry. 

Manufacturing  Processes. — In  the  macaroni   manufacture  the 


FOOD    INDUSTRIES  IO5 

first  step  is  the  preparation  of  a  coarse  meal  called  "semolina" 
or  "semola."  Wheat  is  cleaned  by  steeping  in  water,  dried  by 
heat,  ground  and  sifted.  The  husks  and  much  of  the  starchy 
flour  are  separated  out  leaving  the  light  amber,  glutenous  part 
resembling  a  meal  rather  than  flour.  As  a  rule  manufacturers 
of  macaroni  buy  their  semola  from  millers,  rather  than  do  their 
own  grinding.  The  best  macaroni  is  made  by  blending  various 
grades  of  semola  much  as  flour  is  blended  for  breadmaking. 
The  semola  is  then  put  into  an  iron  mixer,  moistened  with  the 
smallest  possible  quantity  of  hot  water  and  thoroughly  mixed 
by  machinery  for  about  7  minutes  or  until  the  dough  has  a  smooth 
and  tough  appearance.  The  mass  is  kneaded  for  a  few  minutes 
and  is  transferred  to  a  cylinder.  Pressure  descends  upon  the 
dough,  forcing  it  in  strings  slowly  through  the  perforated  plate 
which  forms  the  bottom  of  the  cylinder.  The  form  of  this  plate 
fixes  the  character  of  the  macaroni.  If  the  holes  contain  a  steel 
pin  or  conical  blade  the  dough  takes  the  form  of  a  pipe-stem  and 
is  known  as  tube  macaroni.  Holes  without  pins  give  solid  mac- 
aroni and  smaller  holes  produce  spaghetti  and  vermicilli.  A 
flat  opening  sometimes  takes  the  place  of  'a  round  hole  and  ribbon 
forms  are  made.  When  the  strings  of  paste  are  the  proper  length 
they  are  cut  either  by  hand  or  by  automatic  rotary  knives.  The 
macaroni  is  then  thrown  over  reed  poles  to  dry.  When  the 
weather  is  fine  it  is  left  exposed  to  the  sunlight  for  about  two 
hours.  When  partly  dry,  it  is  put  into  underground  vaults  and 
kept  in  this  damp  place  for  about  12  hours  or  until  the  dough 
has  lost  some  of  its  brittleness  and  is  once  more  pliable.  The 
poles  over  which  the  macaroni  hangs  are  then  carried  to  store- 
houses where  they  remain  until  the  strings  have  a  horn-like  tough- 
ness. They  are  now  ready  to  be  inspected,  sorted,  weighed  and 
packed  for  shipment.  In  case  of  bad  weather  the  macaroni  is 
dried  under  cover  for  a  longer  period.  The  yellow  color  is  pro- 
duced by  the  use  of  saffron  or  of  a  coal  tar  dye. 

Domestic  Macaroni. — There  is  a  constant  increasing  demand 
for  macaroni  made  in  the  United  States.  The  hardest  variety 
of  wheat  is  used  especially  the  hard  wheat  of  Kansas  and  that 


IO6  FOOD    INDUSTRIES 

grown  in  the  semi-arid  land.  The  drying,  especially  in  the  eastern 
states  is  done  entirely  indoors,  the  lengths  being  hung  over 
wooden  rods  in  heated  apartments  through  which  currents  of  air 
are  driven.  The  product  is  very  satisfactory  and  the  sanitary 
conditions  connected  with  the  manufacture  are  largely  in  advance 
of  those  under  which  many  imported  brands  are  produced. 

Judging"  duality. — A  good  quality  of  macaroni  should  have  a 
soft  yellowish  color,  should  be  rough  in  texture,  elastic,  hard,  and 
should  break  with  a  smooth,  glassy  fracture.  In  boiling  it  should 
double  its  original  size  and  should  not  become  pasty  or  adhesive. 

As  a  Food. — Macaroni  is  a  very  palatable  and  nutritious  food. 
It  can  be  kept  for  a  length  of  time  without  deterioration  and  is 
comparatively  inexpensive.  Being  high  in  protein  it  can  readily 
replace  meat  in  the  diet. 


CHAPTER  VIII. 


LEAVENING  AGENTS. 

Early  in  the  history  of  the  human  family,  it  was  found  that 
in  order  to  make  bread  easy  to  masticate  and  more  readily  digest- 
ible, it  must  be  puffed  up  before  it  was  baked.  This  could  best 
be  accomplished  by  a  gas  with  heat  to  expand  it.  C(X  was  the 
first  gas  used,  obtained  through  the  agency  of  yeast,  and  nothing 
has  ever  been  found  that  can  equal  its  action  as  a  leavening  agent. 

ADVANTAGES. — I.  CO2  is  generated  by  the  action  of  the  yeast 
enzyme  on  the  carbohydrate  of  the  meal  or  flour,  so  no  foreign 
substance  is  introduced  into  the  dough. 

II.  The  slow  liberation  of  the  gas  causes  it  to  have  its  full 
effect  as  a  leavening  agent. 

III.  The   by-products   produced   during    fermentation   give   a 
pleasant  taste. 

IV.  Bread  made  by  yeast  is  more  easily  digested. 
DISADVANTAGES. — I.  The  time  required  for  leavening  is  long. 

II.  Careful  watching  and  studying  of  favorable  conditions  for 
the  growth  of  yeast  are  necessary  or  the  result  will  be  sour  or 
sodden  bread. 

III.  It  involves  a  loss  of  carbohydrate  in  the   formation  of 
products  which  are  volatile  at  the  baking  temperature. 

IV.  As  yeast  is  a  living  organism,  it  is  impossible  to  calculate 
the  amount  of  gas  produced. 

Chemical  Agents. — The  necessity  of  sometimes  raising  bread 
quickly  has  led  to  a  study  of  chemical  agents  which  will  produce 
CO2.  With  this  method  the  gas  is  liberated  in  the  presence  of 
water  by  the  action  of  an  acid  or  acid  salt  on  a  carbonate,  usually 
in  the  form  of  a  bicarbonate.  The  salt  resulting  from  the  chem- 
ical action  of  the  acid  and  base  remains  in  the  dough. 

ADVANTAGES. — I.  The  time  is  shortened.  In  a  few  minutes  a 
light,  spongy  dough  can  be  prepared  which  would  require  hours 
by  the  use  of  yeast  fermentation. 

II.  No  loss  of  the  carbohydrate  is  involved. 


IO8  FOOD   INDUSTRIES 

III.  It  is  possible  to  calculate  the  amount  of  gas  which  may 
be  produced  if  the  composition  of  the  chemical  reagents  is  known. 

DISADVANTAGES. — I.  The  taste  is  not  as  good  as  that  of  bread 
raised  by  yeast. 

II.  The  product  is  not  as  readily  digestible. 

III.  The  residue  resulting  from  the  chemical  reaction  remains 
in  the  loaf.    As  these  residues  have  no  nutritive  value,  they  can 
only  be  regarded  as  waste  products. 

Early  Use  of  Chemical  Agents. — Long  before  the  scientific  inves- 
tigation along  the  line  of  these  reagents  was  begun,  the  house- 
wife was  making  use  of  the  same  principle  in  the  utilization  of 
sour  milk  and  saleratus  to  lighten  dough.  Although  this  method 
was  very  effective,  it  had  two  serious  drawbacks:  I.  The  acidity 
of  the  milk  was  apt  to  be  over-estimated.  Lactic  acid  is  caused 
by  the  action  of  bacteria  in  milk  on  the  lactose  or  milk  sugar. 
C,,HMOn.H20—  4C.H.O.. 

When  0.9  per  cent,  is  formed  the  action  is  stopped,  the  lactic 
acid  acting  as  a  preservative.  In  sour  milk  as  used  for  cooking 
purposes,  the  acidity  rarely  exceeds  0.4-0.5  per  cent.  As  a  rule 
too  large  an  amount  of  saleratus  was  used  thus  giving  an  excess 
of  alkali.  This  affected  the  taste  and  interfered  with  protein 
digestion.  2.  The  saleratus  of  to-day  is  not  KHCO3,  but  a 
cheaper  and  stronger  compound  NaHCO3,  approximately  four 
parts  of  which  according  to  the  molecular  weight,  will  do  the 
work  of  five  parts  of  the  potassium  compound.  Old  recipes 
should,  therefore,  be  reduced  to  y$  of  the  amount  suggested. 

Baking  Powders. — The  introduction  of  baking  powders  some 
fifty  to  sixty  years  ago  was  a  great  advantage  although  the  early 
powders  were  very  crude.  The  first  one  prepared  had  for  its 
ingredients  Na2CO3  and  H2SO4,  but  this  proved  too  troublesome 
to  be  practical.  Liebig  suggested  the  use  of  the  NaHCO8  and 
HC1  which  would  give  a  residue  of  NaCl,  a  perfectly  harmless 
product.  The  bicarbonate  was  found  to  be  so  satisfactory  that 
its  use  has  continued  to  the  present  time,  but  experimentation 
soon  proved  that  the  acid  could  not  be  used.  Commercial  HCl 
almost  invariably  contains  traces  of  arsenic,  minute  quantities  of 


FOOD   INDUSTRIES  ICK) 

which  could  be  found  in  the  dough.  Another  acid  was  sought, 
one  which  could  be  effective,  comparatively  cheap,  with  good 
keeping  qualities  and  which  would  give  a  harmless  residue.  Tar- 
taric  acid  was  finally  chosen.  It  was  expensive  and  difficult  to 
keep  but  it  was  effective  and  harmless.  Bicarbonate  of  soda  and 
tartaric  acid  were  tried,  both  in  the  powder  form.  For  the  sake 
of  convenience  these  powders  could  be  mixed  together.  When 
dry,  they  did  not  exert  any  effect  on  each  other  but  atmospheric 
moisture  was  so  quickly  absorbed,  that  chemical  action  took  place 
and  much  carbon  dioxide  was  lost.  An  early  improvement  was 
the  addition  of  starch  or  some  other  substance  having  hygro- 
scopic property.  Starch  absorbs  moisture  readily  and  will  also 
tend  to  keep  apart  the  particles  of  the  acid  and  base.  Another 
improvement  was  soon  made.  Tartaric  acid  was  found  to  be 
harmless  and  efficient  but  it  was  expensive  and  objectionable 
from  a  practical  standpoint.  On  account  of  its  great  solubility, 
too  rapid  evolution  of  gas  occurred.  The  acid  potassium  salt, 
cream  of  tartar,  was  less  expensive,  very  effective  and  perfectly 
harmless.  As  it  was  not  so  soluble,  less  loss  occurred.  These 
were  known  as  the  tartrate  powders. 

Tartrate  Powders. — The  first  powder  of  commercial  impor- 
tance contained  three  ingredients,  bicarbonate  of  soda,  cream  of 
tartar  and  starch  as  a  filler.  Much  advertising  led  to  a  rapid 
growth  in  the  use  of  these  powders  and  in  a  short  time  they 
became  very  popular.  The  method  of  manufacture  was  simple 
and  the  profits  were  enormous.  Chemistry  was  searched  for 
other  combinations  which  could  be  used  for  leavening  bread. 
Two  acid  salts  were  soon  discovered  which  could  be  substituted 
for  cream  of  tartar. 

1.  Phosphate  and  Alum  Pozvders. — Calcium  acid  phosphate,  a 
salt  of  about  the  same  strength  as  cream  of  tartar,  but  cheaper  in 
price. 

2.  Potash  alum,  a  salt  of  great  leavening  power  and  very  low 
in  cost. 

Formulae  were  devised  by  chemists  which  made  possible  the 
use  of  either  one  or  both  of  these  salts  in  combination  with  bi- 


IIO  FOOD    INDUSTRIES 

carbonate  of  soda,  starch  being  added  as  a  filler.  The  powders 
were  known  as  the  phosphate,  the  alum  phosphate  and  the 
straight  alum  powders. 

The  introduction  of  less  expensive  salts  and  the  simplicity  of 
the  process  of  manufacture  led  hundreds  of  individuals  and  com- 
panies into  the  baking  powder  business  and  great  competition 
followed.  Until  the  passing  of  the  law  prohibiting  their  use, 
there  were  many  straight  alum  powders  on  the  market.  They 
contained  starch  as  filler,  bicarbonate  of  soda  and  potassium, 
sodium  or  ammonium  aluminium  sulphate.  They  were  very  ef- 
fective but  were  found  so  objectionable  on  account  of  the  amount 
of  alum  present  that  their  sale  has  been  practically  abolished. 

The  powders  on  the  market  at  the  present  time  are  tartrate, 
phosphate  and  alum  phosphate.  There  has  been  much  contro- 
versy as  to  the  relative  merits  of  these  powders,  the  chief  point 
of  discussion  being  the  residue,  "What  is  it?"  "What  amount  is 
present?"  "Is  it  harmful?"  A  glance  at  the  following  reactions 
and  table  will  give  some  idea  of  the  relative  value. 

TARTRATE  POWDER. 

188  84  54  282  44 

KHC4H4O6  +   NaHCO,  +  3H2O  — >  NaKC4H4O6,4H2O  H    CO.2 

20  per  cent,  filler. 

i  level  T.  of  powder  weighs  3.00  grams  and  contains  20  per 
cent,  of  starch.  This  yields  approximately  0.4  gram  CO.,  or 
200  cubic  centimeters  at  o°  C.,  which  becomes  273  cubic  centi- 
meters at  100°  C.  the  highest  temperature  of  the  oven.  The 
residue  of  crystallized  Rochelle  Salts  amounts  to  2.5  grams. 

PHOSPHATE  POWDER. 

234  168  180 

CaH4(PO4)2  -f  2NaHC(X  +  ioHaO  — > 

136  358  88 

CaHP04  -f  Na2HP04,i2H20  +  2CO2 

CaHPO4  is  insoluble  in  water;  it  requires  free  acid  for  solution. 

i  level  T.  of  powder  weighs  4.4  grams  and  contains  25  per 

cent,  of  starch.     This  yields  approximately  0.72  gram  CO2  or 


FOOD    INDUSTRIES 


III 


355  cubic  centimeters  at  o°  C.  which  becomes  485  cubic  centi- 
meters at  1 00°  C.  the  highest  point  of  the  oven.  The  residue  of 
phosphates  weighs  4.05  grams. 

ALUM  PHOSPHATE  POWDER. 

475  234  336 

(NH4)2A12(S04)4  +  CaH4(P04)2  +  4NaHCO,  + 

144  245  192 

8H20  —  A12(P04)2  +  CaS04,2H20  + 

132  644  176 

(NH4)2S04  +  2Na2S04,ioH20  +  4CO2 

i  level  T.  of  powder  weighs  2.85  grams  and  contains  33^/3  per 
cent,  of  starch.  This  yields  approximately  0.32  gram  CO2  or 
160  cubic  centimeters  at  o°  C.  which  becomes  218  cubic  centi- 
meters at  100°  C.  the  highest  point  of  the  oven.  Residue  weighs 
2.17  grams. 


Weight  of 
i  T.  of 
powder 

Weight  of 
i  T.  of 
powder 
less  the 
filler 

Weight 
of  CO2 

Volume 
of  C02 
at  o°  C. 

Volume 
of  C02  at 
the  oven 
tempera- 
ture 

Weight 
of  the 
residue 

Remarks 

Tartrate  .  . 

3  grains 

2.4  grams 

0.4  gram 

200  C.C. 

273  c.c. 

2.5  grams 
All  soluble 
in  water. 

Residue  contains 
water  of  crys- 
tallization. 

Phosphate 

4.4  grams 

3.3  grams 

0.72  gram 

355  c.c. 

485  c.c. 

4.05  grams 
27.5$  insol- 
uble   in 
water. 

Residue  contains 
water  of  crys- 
tallization. 

Alum 
phosphate 

2.85  grams 

1.9  grams 

0.32  gram 

160  c.c. 

218  c.c. 

2.17  grams 
36.6  *jt  insol- 
uble   in 
water. 

Residue  contains 
water  of  crys- 
tallization. 

Relative  Efficiency. — I.  Alum  phosphate  powders  are  the 
cheapest,  but  they  do  not  keep  well.  They  contain  alum  which 
is  supposed  to  have  a  deleterious  effect  on  the  system  and  leave 
a  residue  which  is  partly  insoluble  in  water. 

II.  Phosphate  powders  are  cheap,  but  they  do  not  keep  well 
and  leave  a  residue  which  to  some  extent  is  insoluble. 


112  FOOD    INDUSTRIES 

III.  Tartrate  powders  are  expensive,  but  they  keep  well  so 
are  effective  when  old.  They  yield  a  residue  of  Rochelle  Salts 
which  is  soluble  in  water. 

Tartrate  powders  may  be  prepared  at  home  by  thoroughly 
mixing  ^-pound  of  cream  of  tartar,  T4-pound  of  bicarbonate  of 
soda  and  *4~P°und  of  starch  or  lactose.  Lactose  has  been  found 
to  be  very  effective  as  a  filler.  It  has  great  lasting  power  but  is 
more  expensive. 

Ammonia  Powders. — Bakers  are  now  using  ammonia  carbonate 
very  effectively  as  a  leavening  agent.  It  has  the  great  advantage 
of  leaving  no  residue,  but  must  be  used  in  very  small  quantities 
or  the  product  will  taste  of  ammonia. 

(NHJ2C03  ~  2NH3  +  C0.2  +  H,0. 

Cream  of  Tartar. — Almost  all  of  the  cream  of  tartar  and  tar- 
taric  acid  used  in  this  country  is  imported,  the  largest  amount 
coming  from  Germany  and  France.  They  are  by-products  of 
the  wine  industry  being  obtained  from  a  certain  kind  of  sour 
wine.  Cream  of  tartar  or  potassium  bitartrate  is  a  normal  con- 
stituent of  grapes,  occurring  in  comparatively  large  amounts. 
When  the  fruit  is  crushed  and  pressed  in  the  preparation  of 
wine,  most  of  the  tartrate  salts  being  soluble  passes  out  with  the 
juice.  There  is  no  tendency  for  it  to  become  insoluble  and  pre- 
cipitate out  in  crystalline  form  until  the  grape  juice  reaches  5-6 
per  cent,  of  alcoholic  strength.  This  occurs  during  the  fermen- 
tation process.  It  is  customary  to  float  branches  of  the  grape 
vine  in  the  fermenting  vats.  As  the  alcohol  increases,  gradually 
cream  of  tartar  is  deposited  upon  the  sides  of  the  vat  and  on  the 
floating  branches.  The  crystals  carry  down  with  them  the  color 
of  the  wine.  They  are  known  commercially  as  "argol."  There  are 
usually  from  one  to  three  inches  of  a  dark  deposit  at  the  bottom 
of  a  full  barrel  of  new  wine  after  it  has  stood  long  enough  to 
settle,  called  the  "lees."  From  argol,  cream  of  tartar  is  made. 
"Lees"  contains  a  larger  amount  of  calcium  tartrate  and  is  used 
more  extensively  for  the  production  of  tartaric  acid. 

Argol  is  not  pure  cream  of  tartar  as  it  carries  down  in  pre- 
cipitating, other  constituents  of  the  grape.  These  impurities 


FOOD    INDUSTRIES  113 

must  be  removed.  In  the  process  of  refining,  the  crystals  of 
argol  are  powdered,  dissolved  in  boiling  water  and  filtered  to 
remove  dirt  and  other  foreign  matter.  The  color  can  be  removed 
with  egg  albumin  or  by  filtering  while  hot  through  bone-black. 
The  solution  is  then  ruri  into  shallow  receivers  and  as  the  clear 
liquid  cools,  cream  of  tartar  separates  out  and  is  deposited  in 
thick  masses  of  crystals.  These  crystals  may  be  further  purified 
by  again  dissolving  in  hot  water  and  recrystallizing.  When  all 
the  impurities  are  removed,  the  crystals  are  powdered  in  a  mill 
and  are  then  ready  for  the  market. 

Tartaric  Acid. — Tartaric  acid  may  be  prepared  from  the  lees 
by  the  action  of  sulphuric  acid.  The  calcium  is  removed  in  the 
form  of  a  sulphate. 

CaC4H406  -f  H2S04  •—  H2C4H4O6  +  CaSO, 

Tartaric  acid  is  used  largely  in  pharmacy  and  in  the  textile  in- 
dustry, either  as  the  acid  or  as  tartar  emetic  in  certain  dyeing 
processes  and  in  calico  printing. 

Acid  Phosphate  of  Lime. — Acid  phosphate  of  lime  occurs  in 
different  forms.  The  soluble  acid  phosphate  as  used  in  the  bak- 
ing powder  industry  does  not  occur  in  nature,  but  must  be  manu- 
factured. The  skeletons  of  animal  life  are  largely  employed  for 
this  purpose.  Here  calcium  phosphate  Ca3(PO4)2  appears  in 
a  form  insoluble  in  water,  but  which  can  be  readily  made  soluble 
by  treatment  with  an  acid. 

Cas(P04),  +  2H2S04—  CaH4(P04),'+  2CaSO4 

insoluble  soluble 

The  material  utilized  in  this  industry  is  usually  obtained  from 
certain  sections  of  the  country  where  large  deposits  of  phos- 
phate of  lime  have  been  found.  This  has  been  caused  by  sharks 
and  other  forms  of  animal  life  having  been  deposited  in  past 
ages,  and  through  the  process  of  weathering  all  organic  matter 
has  disappeared,  leaving  only  the  material  which  has  constituted 
the  frame  work.  This  material  is  dug  up  and  changed  to  a  form 
which  can  be  utilized  in  the  baking  powder  industry. 

Bicarbonate  of  Soda. — The  preparation  of  soda  constitutes 
to-day  one  of  our  largest  and  most  important  industries.  An 


114  FOOD    INDUSTRIES 

alkali  has  been  used  for  cleaning  purposes  by  the  housewife,  for 
many  centuries,  but  this  represents  only  about  one  per  cent,  of 
the  soda  manufactured.  It  is  also  needed  in  many  industries 
such  as  soap-making,  glass  manufacture  and  in  the  bleaching  of 
cotton  and  linen  goods. 

The  original  alkali  used  was  potassium  carbonate  obtained 
from  potassium  salts  which  are  widely  spread  throughout  plant 
life.  The  early  housewife  obtained  her  supply  from  the  ashes 
of  her  wood  fire.  Boiling  water  was  poured  over  the  dead  embers 
of  the  fire,  and  the  solution  was  boiled  down  giving  a  lye  which 
could  be  used  for  cleansing  purposes.  For  many  years,  the 
manufacturer  was  forced  to  depend,  also,  on  the  leaching  of 
wood  ashes  or  on  natural  deposits  of  potash  which  have  been 
found  in  certain  parts  of  the  world.  The  largest  deposits  occur 
on  the  western  coast  of  South  America  and  in  the  region  of 
North  Germany  which  has  Starsfurt  as  the  center. 

It  was  not  until  the  i8th  century  that  another  alkali  was  found 
to  take  its  place.  This  was  discovered  by  the  Spaniards  who 
prepared  it  by  burning  to  ash  a  sea-weed  found  along  their  coast. 
It  contained  a  sodium  compound  which  yielded  a  carbonate  on 
heating.  The  soda  compound,  being  stronger  and  cheaper  than 
potash,  was  readily  received  by  the  manufacturers  and  used  by 
them,  until  the  early  days  of  the  iQth  century.  Warfare  at  that 
time  interfered  with  commerce  and  Spain  being  hostile,  the 
French  manufacturers  were  cut  off  from  their  source  of  supply. 
Napoleon  was  determined  to  get  some  means  of  replacing  this 
alkali  and  as  France  was  poor  in  mineral  deposits,  he  offered  a 
reward  for  the  discovery  of  a  practical  process  for  making 
sodium  carbonate.  Everything  used  in  the  manufacture,  how- 
ever, must  be  obtained  in  France.  Many  chemists  worked  at 
this  problem  and  a  process  was  finally  discovered  by  Le  Blanc 
which  is  used  in  many  places  at  the  present  time. 

Le  Blanc  Method. — Le  Blanc  used  in  the  preparation  of  soda, 
dry  salt  which  he  obtained  from  the  sea,  by  the  process  of  evap- 
oration.    He  then  mixed  together  salt  and  sulphuric  acid. 
2NaCl  -f  H2S04  —  Na2S04  -f  2HC1 


FOOD    INDUSTRIES  115 

Na2SO4  was  known  as  the  salt  cake.  It  was  broken  up  and 
mixed  with  powdered  coal  and  limestone  and  was  then  treated 
in  a  reverberatory  furnace. 

Na.2S04  +  2C  —  Na2S  +  2CO, 
Na.2S  -f  CaCO3  —  Na.2CO3  +  CaS 

Na-jCOg  an  impure  form,  known  as  soda  ash,  could  be  dissolved 
out  and  the  water  afterwards  evaporated.  To  obtain  pure 
Xa.,CO3,  the  soda  ash  must  be  again  heated  with  coal  and  other 
soda  compounds  be  changed  to  the  carbonate  form. 

Bicarbonate  of  soda  can  be  easily  obtained  from  sodium  car- 
bonate. 

Na2CO3  -+  H,O  +  CO,  —-  2NaHCO, 

Hydrochloric  acid  was  practically  unknown  commercially  until 
the  invention  of  the  Le  Blanc  process  of  soda  manufacture. 
At  first  it  was  allowed  to  escape  into  the  air  and  being  washed 
down  by  rain  it  found  its  way  into  neighboring  streams.  This 
soon  caused  the  destruction  of  animal  and  plant  life  and  was 
also  a  waste  of  a  valuable  by-product.  Later  it  was  discovered 
that  HC1  could  be  run  into  water  and  sold.  This  opened  up  a 
new  industry  and  did  much  toward  making  the  Le  Blanc  method 
a  commercial  success. 

When  more  HC1  was  produced  than  was  needed,  it  was  soon 
found  that  from  it  chloride  of  lime  could  be  prepared,  and  a 
valuable  disinfectant  and  bleaching  agent  was  placed  upon  the 
market. 

Value  of  the  Le  Blanc  Process. — I.  The  raw  materials  salt, 
coal,  limestone  and  sulphuric  acid  are  common  and  inexpensive. 

II.  The  furnace  and  plant  can  be  put  up  at  a  fairly  low  price. 

III.  The    by-products    are    important    and    have    done    much 
toward  keeping  this  process  in  existence. 

Solvay  Process. — The  Solvay  method  of  preparing  sodium 
carbonate  was  invented  in  1860  by  a  Belgian  named  Solvay,  and 
is  a  serious  rival  of  the  Le  Blanc  process.  Scattered  throughout 
the  world  are  large  deposits  of  salt,  sometimes  in  the  dry  state 
as  in  the  salt  mines  of  Germany  and  England,  at  other  times  in 
the  form  of  brine.  Brine  wells  occur  more  extensivelv  and  as 


Il6  FOOD    INDUSTRIES 

the  Le  Blanc  method  required  dry  salt,  it  was  found  very  trouble- 
some to  evaporate  the  water.  The  Solvay  process  can  make 
use  of  the  brine.  This  has  been  a  great  benefit  to  America  for 
brine  wells  are  abundant  in  Michigan,  Louisiana  and  New  York 
State.  Syracuse  is  an  important  center  in  the  American  soda 
industry.  Brine  is  also  much  easier  to  handle.  It  is  pumped 
to  the  surface,  saturated  with  ammonia,  and  then  with  carbon 
dioxide. 

NaCl  +  HtO  +  NH3  +  CO,  —  NaHCO.,  H    NH4C1. 

NaHCOs  is  separated  out  by -filtration. 

If  sodium  carbonate  is  wanted  the  bicarbonate  is  heated. 
2  NaHCO,  —  Na2CO3  +  H2O  CO,. 

The  ammonium  chloride  obtained  in  this  process  can  be  de- 
composed by  heating  with  quicklime,  and  the  ammonia  given  off 
is  again  used  for  the  treatment  of  another  batch  of  brine. 

This  process  is  cheaper  than  the  Le  Blanc  and  furnishes  a 
purer  product. 

Niagara  Process. — By  the  use  of  electricity,  a  method  of  pre- 
paring soda  has  been  discovered,  which  is  a  serious  rival  to 
both  the  Le  Blanc  and  Solvay  processes.  Brine  is  here  run 
into  partitioned  tanks  containing  electrodes.  When  the  current 
is  turned  on  ionization  of  the  salt  occurs. 

NaCl  +  H20  —  NaOH  +  HC1. 

NaOH  passes  to  the  negative  pole  in  one  partition  as  it  carries 
a  positive  change  and  HC1  goes  to  the  positive  pole  in  the  other 
partition. 

Caustic  soda  can  readily  be  utilized  in  the  preparation  of  the 
carbonate  and  the  bicarbonate. 

2  NaOH  4-  CO,  —  Na,CO,  +  H,O, 
Na2C03  +  H,0  -f-  CO,  —  2  NaHCO.s 

In  this  industry  HC1  can  again  be  used  as  a  by-product  for  the 
preparation  of  chloride  of  lime  or  can  be  utilized  in  the  acid 
form. 


CHAPTER  IX. 


STARCH  AND  ALLIED  INDUSTRIES. 

Starch  is  one  of  the  most  widely  diffused  substances  in  the 
vegetable  kingdom.  With  the  exception  of  the  fungi,  it  has  been 
found  in  varying  amounts  in  every  plant  that  scientists  have  so 
far  examined.  It  occurs  in  relatively  large  amounts  in  different 
parts  of  the  plant  as  in  the  seed  (cereals),  the  root  (cassava), 
the  tuber  (potato),  the  fruit  (banana),  the  stem  (celery,  rhu- 
barb, sago),  and  in  the  leaves  (spinach). 

Composition  and  Formation. — See  Chapter  I,  Food  Principles. 

Physical  Characteristics. — To  the  naked  eye,  starch  has  the 
appearance  of  a  glistening  white  powder.  It  is  neutral  to  litmus, 
has  no  odor  or  taste,  does  not  crystallize  and  has  a  harsh  feeling 
when  rubbed  between  the  fingers.  When  seen  through  a  micro- 
scope, it  consists  of  granules  of  various  forms,  round,  oval,  etc., 
differing  greatly  in  size,  according  to  the  source.  This  has  served 
as  a  valuable  means  of  identifying  starch.  Although  the  size 
and  shape  may  differ,  all  starch  granules  have  a  characteristic 
appearance.  They  are  arranged  in  layers  around  a  central  nu- 
cleus. The  outside  consists  of  a  substance  closely  resembling 
cellulose  and  within  the  granule  or  package  is  found  the  true 
starch. 

Physical  and  Chemical  Properties. — I.  Insoluble  in  cold  water. 

II.  With  iodine,  starch  gives  a  characteristic  blue  color. 

III.  Starch   absorbs   moisture    from   the    atmosphere   until    it 
contains  approximately  18  per  cent.     In  very  damp  weather,  it 
has  been  found  to  absorb  a  much  larger  quantity. 

IV.  When  heated  dry  to  200°  C.  or  more  it  is  converted  into 
dextrin. 

V.  When  heated  in  the  presence  of  water,  the  contents  of  the 
granules  swell  enormously  owing  to  a  large  absorption  of  water, 
and  cause  the  rupture  of  the  outer  wall.     The  starch  freed  from 
the  package,  forms  a  viscous  liquid  known  as  starch  paste. 

Uses. — While  its  place  in  the  diet  would  alone  make  starch  an 


I  1 8  FOOD    INDUSTRIES 

important  article  of  commerce,  the  manufacturer  finds  many 
another  market  for  his  product.  It  is  used : 

In  laundries. 

For  food  such  as  puddings,  sauces  and  jellies. 

For  candies  such  as  gum  drops  and  lozenges. 

In  baking  powders. 

In  the  textile  industry  for  stiffening  and  finishing  fabrics. 

In  wall  paper  manufacture  as  a  filler,  finisher  and  size. 

For  cosmetics,  asbestos,  soaps  and  adhesives. 

In  brewing  beer,  ales  and  in  the  manufacture  of  alcohol. 

For  the  manufacture  of  dextrin  and  glucose. 

Source  of  Supply. — While  starch  is  so  widely  distributed  in  the 
vegetable  kingdom,  there  are  comparatively  few  plants  that  can 
be  utilized  as  a  source  of  supply  for  the  manufacture.  In  look- 
ing for  his  raw  material,  the  starch  producer  must  consider  sev- 
eral important  points:  ist,  the  ease  with  which  the  plant  can  be 
grown  in  his  locality;  2nd,  the  amount  of  starch  yielded  by  the 
plant ;  3rd,  the  ease  of  extraction ;  4th,  the  presence  of  other 
constituents  such  as  protein  and  oil,  which  makes  the  process 
difficult. 

With  these  points  in  mind,  the  European  manufacturer 
chooses  the  potato,  wheat  and  rice.  The  American  uses  corn 
and  to  a  limited  extent  the  potato  and  wheat.  In  the  East  and 
West  Indies  the  cassava  furnishes  the  chief  source  of  starch. 
The  arrowroot  is  utilized  in  the  West  Indies  and  parts  of  South 
America,  and  the  sago  in  the  East  Indies. 

POTATO   STARCH. 

The  potato  is  a  valuable  source  of  starch  on  account  of  the 
great  ease  of  extraction.  The  starch  content  is  comparatively 
low  as  compared  with  corn  and  wheat,  but  protein,  mineral  mat- 
ter and  oil  are  present  in  such  small  amounts  that  they  do  not 
interfere  with  manufacturing  processes.  As  a  rule  only  about 
20  per  cent,  of  starch  is  found  in  the  potato,  although  in  certain 
parts  of  Germany  the  starch  content  has  reached  from  25-29 
per  cent. 

Potatoes  can  be  grown  very  easily  in  temperate  climates  such 


FOOD   INDUSTRIES  119 

as  Germany,  England,  Scotland  and  Ireland.  In  the  United 
States,  Maine  is  noted  for  the  production  of  a  high  quality  po- 
tato and  Wisconsin  and  Colorado  grow  the  potato  largely  for 
the  starch  industry.  The  following  demonstration  may  be  used 
to  illustrate  the  simplicity  of  the  method  used : 

Extraction  of  Starch. — Clean  and  remove  the  skin  from  a  small 
potato.  Rub  it  on  an  ordinary  grater.,  collect  the  gratings  in  a 
beaker  of  cold  water,  strain  and  allow  the  cloudy  liquid  to  stand 
until  the  starch  settles.  Pour  off  the  liquid.  The  starch  can  be 
purified  by  the  addition  of  water,  thoroughly  mixing  and  allow- 
ing the  starch  to  again  settle.  Remove  the  water  by  nitration 
and  dry  the  starch  with  low  heat. 

Although  the  manufacturer  uses  more  or  less  complicated 
machinery  to  carry  out  these  operations,  the  commercial  pro- 
cesses are  practically  the  same. 

Processes  in  Manufacture. — I.  Cleaning. — The  washing  of  po- 
tatoes must  be  thorough  or  the  quality  of  the  starch  will  suffer. 
The  adhering  dirt  and  sand  are  carefully  removed  by  washing 
in  revolving  wooden  drums,  so  constructed  that  the  water  carry- 
ing dirt  and  other  impurities  can  escape  through  narrow  open- 
ings. Inside  the  drums,  devices  such  as  bristle  or  wire  brushes, 
or  revolving  arms  which  rub  the  potatoes  together,  are  some- 
times used  to  assist  in  the  cleansing. 

II.  Rasping. — The  potatoes  are  reduced  to  a  pulp  in  machines 
called  raspers.    These  are  usually  revolving  cylinders  containing 
saw  blades  or  knife  edges  to  assist  in  the  pulping  process.   Water 
is  added  at  the  time  of  rasping  and  the  starch  pulp  is  fed  to  a 
sifting  machine. 

III.  Sifting. — Shaking  tables  covered  with  gauze  separate  the 
rch  grains  from  the  potato  pulp.     The  pulp  can  be  pressed 

and  dried.  It  is  sold  as  a  low  grade  cattle  food.  The  starch 
suspended  in  water  passes  through  the  sieves  to  settling  tanks. 
When  it  has  settled  in  a  firm  mass,  it  can  be  broken  up  and  sent 
at  once  to  a  drying  kiln  or  can  be  further  refined. 


120 


FOOD    INDUSTRIES 


All  root  starches  follow  the  same  principle  in  the  extraction 
of  the  starch. 

TAPIOCA. 

Tapioca  is  an  important  food  product  prepared  from  the 
starch  of  the  cassava,  a  plant  grown  largely  in  Brazil  and  other 
tropical  countries.  The  extraction  of  the  starch  is  carried  out 
by  the  processes  of  grinding  and  washing  with  water,  similar  to 
those  described  under  potato  starch.  The  product  is  sometimes 
known  as  Brazilian  arrowroot.  In  the  manufacture  of  tapioca, 
the  starch  while  still  damp  is  placed  in  shallow  pans  and  sub- 
jected to  low  heat.  •  As  the  moisture  is  driven  off,  the  tempera- 


Fig.  25.— Sheds  and  Board  Used  for  Drying  the  Tapioca.     (Courtesy  of  The  Spice 
Mill  Publishing  Co.) 

ture  is  gradually  raised  until  the  starch  granules  burst  and  ad- 
here together,  forming  the  mass  into  small  irregularly  shaped 
translucent  kernels.  A  similar  product  may  be  obtained  by  mak- 
ing a  starch  paste,  subjecting  it  to  heat,  and  forcing  it  through 
metal  screens  from  which  it  is  dropped  and  cooled.  Tapioca  is 
placed  on  the  market  in  various  forms  according  to  the  amount 
£>f  heat  used  and  differences  in  mechanical  operations. 


FOOD    INDUSTRIES 


121 


Starch  derived  from  other  sources  may  be  subjected  to  the 
same  treatment  and  an  equally  nutritious  product  be  obtained. 
As  genuine  tapioca,  however,  is  always  prepared  from  cassava 
starch,  other  imitative  forms  must  be  classed  as  substitution 
products. 

Outline  of  the  Corn  Products  Industry.— 

I.  Cleaned. 
II.  Kernel  softened  by  steeping. 

III.  Crushed. 

IV.  Separated  by  gravity. 

(1)  Germ  flows  off  from  the  top  with  the  raw  starch 

liquor,  screened  from  the  latter,  dried,  ground, 
pressed. 

(2)  Hulls    flow    off    from    the    bottom    with    the    raw 

starch  liquor,  screened  from  the  latter,  then 
ground  in  burr  mills  and  become  part  of  gluten 
feed. 

(3)  Endosperm  (raw  starch  liquor)  separated  by  grav- 

(  Starch, 
ity  on  tables  into  X 

(  Gluten,  which  with  corn  sol- 
ubles obtained  from  steep- 
ing water,  becomes  part 
of  the  gluten  feed. 

Starch  is  purified  and  sold  as 

I.  Starch— laundry  lump,  crystal,  pearl  powder  etc. 

(    i.  By  process  of  roasting. 
II.   Dextrin     •< 

(  2.  By  use  of  a  dilute  acid. 

Boiled    with   dilute 

acid  0.06  of  i% 
Neutralized. 
Filtered. 
Decolorized. 
Concentrated. 


III.   Glucose  by  process  of  hydrolysis 


122 


FOOD   INDUSTRIES 


CORN  PRODUCTS  INDUSTRY. 

The  abundance  of  the  growth  of  corn  in  the  United  States 
and  the  many  by-products  obtained,  make  it  an  important  source 
of  starch,  although  the  composition  of  the  kernel  involves  elabo- 
rate methods  for  the  extraction. 

The  kernel  of  corn  consists  of  an  outer  coating  called  the  hull, 
the  germ  which  contains  a  comparatively  large  amount  of  oil, 
and  the  endosperm,  where  are  found  starch  and  protein. 

When  received  at  the  factory,  the  corn  contains  some  impuri- 
ties and  the  kernel  is  in  a  dry,  hard  condition. 


Fig.  26. — Steeped  Corn  Running  to  Crushers.     (Courtesy  of  Corn  Products  Refining  Co.) 

Processes  in  Manufacture. — I.  Cleaning. — Corn  like  other 
cereals  contains  a  certain  amount  of  foreign  matter  such  as  bits 
of  corn  cob,  pieces  of  wood,  lint,  dust  and  dirt.  These  are  re- 
moved by  screening,  while  magnets  are  used  for  drawing  out  bits 
of  iron,  nails  and  the  like. 

II.  Steeping. — In  order  to  separate  the  kernel  into  its  com- 


FOOD    INDUSTRIES 


123 


ponent  parts,  the  hard,  dry  grain  must  first  be  softened.  This  is 
accomplished  by  steeping  it  in  water  for  approximately  40  hours 
at  a  temperature  of  110°  F.  Steam  is  injected  to  maintain  the 
circulation  and  to  keep  the  temperature  at  the  desired  degree 
A  very  small  amount  of  acid,  0.005  per  cent.  H2SO3,  is  added  to 
prevent  fermentation.  This  is  afterwards  removed  by  thorough 
washing.  When  the  grain  has  absorbed  sufficient  moisture  to 
cause  a  loosening  and  softening  of  the  various  parts,  the  water 
is  drawn  off,  leaving  the  kernel  of  corn  in  a  moist,  soft  condition. 


Fig.  27.— Crushers.     (Courtesy  of  Corn  Products  Refining  Co.) 

The  steepwater  is  evaporated  and  the  solubles  of  the  corn  are 
incorporated  with  the  gluten  feed.  The  steeped  corn  is  run  to 
the  crushers  (Fig.  26). 

III.  Crushing. — The  softened  grain  is  passed  through  a  mill 
called  the  crusher  (Fig.  27).  It  consists  of  two  large  disks  set 
face  to  face  having  projecting  teeth  and  rotating  in  opposite  di- 
rections. It  is  supposed  to  grind  only  to  a  coarse  meal,  thus 
leaving  the  germ  and  hull  intact. 


I24 


FOOD    INDUSTRIES 


Fig.  28.— Separators.    (Courtesy  of  Corn  Products  Refining  Co.) 


Fig.  29.— Hydraulic  Presses  for  Oil.     (Courtesy  of  Corn  Products  Refining  Co. 


FOOD   INDUSTRIES  125 

IV.  Separation. — The  resulting  mass  is  fed  to  a  long,  narrow 
tank  about  25  feet  long,  4  feet  wide  and  8  feet  deep,  where  tak- 
ing advantage  of  the  difference  in  the  specific  gravity,  a  separa- 
tion of  the  various  parts  is  effected.     The  germ  being  the  light- 
est rises  to  the  top  and  floats  over  the  weir  at  the  end  of  the  tank ; 
the  hulls  sink  to  the  bottom  and  flow  off  with  the  starch  liquor 
(Fig.  28).    The  germs  are  passed  over  screens  or  shakers.    They 
are    then    washed   to    free   them    from   adhering    starch,    dried, 
ground  fine,  heated,  wrapped  in  cloth  and  pressed  (Fig.  29).    The 
pressure  causes  the  oil  to  flow  out,  leaving  the  oil  cake  which  is 
sold  for  cattle  food.     The  oil  is  cleared  of  foots  by  settling  and 
passing  through  a  filter  press.     It  may  be  used  for  the  manufac- 
ture of  soap,  soap  powders,  oil  cloth,  leather,  paints  and  var- 
nishes.    By  further  refining  with  a  treatment  which  removes  the 
free  fatty  acids  and  other  impurities,  corn  oil  can  be  used  for 
edible  purposes  as  a  salad  oil,  for  frying  and  cooking  and  as  a 
shortening  for  bread  and  cake.     In  this  form,  it  is  also  utilized 
for  pharmaceutical  purposes.     By  a  vulcanizing  process,  corn  oil 
yields   a   substance   called   "paragol,"   which   can   be  used   as   a 
rubber  substitute  in  the  preparation  of  such  articles  as  shoes, 
rubber  specialties  and  automobile  tires. 

V.  The  Hulls  and  the  Endosperm. — The  hulls  flow  off  from 
the  bottom  of  the  separator  together  with  the  starch  liquor  (en- 
dosperm)  just  as  did  the  germs  from  the  top  of  the  separator. 
They  then  pass  over  screens,  the  starch  liquor  uniting  with  the 
starch  liquor  of  the  germs.     The  hulls  being  coarse  are  ground 
in  burr  mills,  passed  over  screens,  the  starch  liquor  unites  with 
the  starch  liquor  of  the  germs  and  of  the  hulls,  and  the  ground 
hull  becomes  part  of  the  gluten  feed,  being  mixed  with  the  glu- 
ten and  corn  solubles. 

The  starch  liquor  (endosperm)  contains  the  starch  and  pro- 
tein matter,  which  is  spoken  of  as  gluten  by  the  manufacturer. 
These  must  next  be  separated.  This  is  effected  by  running  the 
starch  liquor  from  the  germs,  hulls  and  ground  hulls,  directly 
upon  tables  from  60-120  feet  long,  3  feet  wide  with  a  decline  of 
about  4  inches.  As  there  is  a  difference  in  specific  gravity,  the 


126 


FOOD    INDUSTRIES 


starch  settles  while  the  liquid  containing  the  protein  flows  over 
the  end  of  the  run  and  is  caught  in  a  tank  below.  The  crude 
corn  protein  is  mixed  with  the  hulls,  filter  pressed,  mixed  with 
the  corn  solubles,  dried,  ground  and  constitutes  gluten  feed. 
The  starch  which  settles  to  the  bottom  of  the  run  is  removed 
by  being  shoveled  while  in  a  solid,  moist  condition.  The  purifi- 
cation can  be  effected  by  the  addition  of  water  and  again  pass- 
ing over  the  runs  on  which  the  starch  settles.  This  process  can 
be  repeated,  until  all  foreign  matter  such  as  traces  of  fat  and 


Fig.  30. — Dripping  Boxes.     (Courtesy  of  Corn  Products  Refining  Co.) 

protein,  are  removed.  Pearl  starch,  that  to  be  used  for  baking 
powder  and  for  certain  classes  of  food  starch,  is  prepared  by 
breaking  up  the  starch  from  the  table  and  placing  it  on  trays 
which  are  put  into  iron  wagons,  run  into  kilns,  and  dried.  The 
lump  starch  and  crystal  iorms  are  prepared  by  mixing  the  starch 
from  the  tables  with  water,  then  running  it  into  boxes  with  per- 
forated bottom  lined  with  cloth  (Fig.  30).  The  boxes  are  allowed 
to  stand  until  the  water  runs  off,  then  turned  over  and  the  thick 


FOOD   INDUSTRIES 


127 


slab  of  starch  is  broken  up  into  cubes  (Fig.  31 ).  These  are  either 
wrapped  in  paper  or  put  in  trays  and  placed  in  drying  ovens, 
where  after  ten  or  more  days  they  are  drawn  out. 


Fig.  31.— Emptying  Starch  from  Drip  Boxes.     Breaking  into  Cubes. 
(Courtesy  of  Corn  Products  Refining  Co.) 

DEXTRINS. 

Dextrins  are  produced  in  the  same  factory  usually  by  the 
simple  process  of  roasting.  The  different  varieties  depend  upon 
the  time  and  heat  applied. 

Uses  for  Dextrins. — For  the  manufacture  of  gums,  glues,  muci- 
lage and  other /adhesives. 

For  cloth,  carpets  and  twine. 

For  leather  dressings,  paper  and  ink. 

For  food  sauces. 

In  the  textile  industry,  in  sizes  for  strengthening  the  fiber  and 
finishing  the  fabric.  Also  for  thickening  colors  for  calico  and 
other  printing. 


128  FOOD   INDUSTRIES 

CORN  SYRUP  OR  GLUCOSE. 

On  account  of  its  source  commercial  glucose  is  known  in  the 
United  States  as  corn  syrup.  The  term  glucose  is  derived  from 
the  Greek  word  "Glykos"  meaning  sweet.  It  is  a  carbohydrate 
of  the  monosaccharid  group,  C6H12O6,  and  is  found  in  nature  in 
the  juice  of  many  plants  such  as  grapes,  cherries  and  sweet  corn. 
Although  it  exists  at  times  in  relatively  large  amounts,  the  com- 
mercial source  of  glucose  is  always  starch  on  account  of  the 
cheapness  of  that  material,  and  the  comparatively  simple  process 
of  manufacture.  In  Europe  glucose  was  first  prepared  from  the 
potato  starch  during  the  early  part  of  the  iQth  century,  and  has 
long  been  looked  upon  as  a  nutritious  food/  It  was  not  until 
after  the  Civil  War,  however,  that  American  manufacturers 
started  experimenting  with  corn  starch  as  a  source  of  supply 
for  glucose.  As  grape  sugar  and  corn  syrup,  it  was  soon  placed 
upon  the  market.  The  products  from  corn  compared  very  fav- 
orably with  those  made  abroad  from  potato  starch  and  so  rapidly 
has  the  manufacture  grown,  that  it  is  now  one  of  our  most  im- 
portant industries. 

Glucose  is  sold  in  the  liquid  form,  either  white  or  colored, 
with  or  without  flavoring,  and  as  a  solid  in  the  powdered  and 
crystalline  form,  all  under  various  trade  names. 

Uses  for  Glucose. — For  confectionery,  syrups,  jams,  jellies,  pie 
filling,  puddings,  preserves  and  mince  meat. 

In  the  brewing  of  beer. 

In  chewing  tobacco. 

In  silvering  glasses  for  mirrors. 

In  liquid  soaps,  hair  tonics,  blacking  and  shoe  polishes. 

In  food  sauces  and  in  the  canning  of  meats. 

For  pastes  and  sizes. 

In  the  tanning  of  leather  and  in  rice  polishing. 

Processes  of  Manufacture — Whether  in  Europe  or  America, 
whether  from  potato  or  corn  starch,  the  manufacturer  must  use 
the  process  of  hydrolysis  to  obtain  glucose.  This  is  accom- 
plished by  heating  starch  in  a  closed  digestor,  with  a  minute 
quantity  of  muriatic  acid.  The  amount  of  acid  used  represents 


FOOD   INDUSTRIES  129 

proportionately  about  a  fifth  of  the  same  acid  contained  in  the 
gastric  juice. 

The  heating  is  continued  until  the  starch  reaction  with  iodine 
has  disappeared.  At  the  present  time,  a  pressure  of  35  pounds 
is  maintained  and  the  operation  at  that  pressure  is  finished  in 
about  five  to  ten  minutes. 

On  the  continent  and  in  England  H2SO4  is  the  agent  used  for 
hydrolysis.  This  is  afterwards  neutralized  with  marble  dust 
which  with  the  acid  forms  an  insoluble  precipitate.  During  the 
process  of  refining  this  precipitate  is  removed. 

H2SO4  +  CaCO3  ~-  CaSO4  +  H2O  +  CO2. 

The  American  manufacturer  prefers  the  use  of  HC1,  although 
it  is  more  expensive.  With  soda  ash  as  a  neutralizing  agent, 
common  salt  is  obtained  as  a  residue,  and  being  perfectly  harm- 
less, the  manufacturer  is  saved  the  trouble  of  removing  it. 
American  glucose,  therefore,  always  contains  sodium  chloride. 
2  HC1  +  Na2C03  «~  2  NaCl  +  H2O  +  CO2. 

After  hydrolysis,  the  glucose  solution  is  filtered  to  remove 
small  amounts  of  fat  and  protein  occurring  in  the  starch,  and  is 
then  decolorized  by  passing  through  bone-black,  a  similar  pro- 
cess to  that  used  in  the  cane  sugar  industry.  It  is  then  evap- 
orated to  various  degrees  of  concentration. 

If  hydrolysis  has  been  continued  until  the  dry  substance  in 
the  liquid  consists  of  at  least  86  parts  of  glucose,  the  product 
after  concentration  instead  of  being  a  syrup,  crystallizes  and 
hardens  into  a  sugar  after  it  has  been  run  into  barrels  or  pans. 


CHAPTER  X. 


THE  SUGAR  INDUSTRY. 

Source. — The  disaccharid  C^H^O^,  known  as  sucrose  or  sac- 
charose, is  found  in  a  large  variety  of  plants.  It  is  so  apt,  however, 
to  be  accompanied  by  a  characteristic  taste  of  the  plant,  or  other 
carbohydrates  such  as  starch,  glucose  or  invert  sugar,  that  unless 
it  appears  in  relatively  large  proportions  and  can  successfully 
be  freed  from  the  taste,  it  does  not  pay  commercially  to  extract 
it.  For  the  supply  of  raw  sugar  the  world  is  largely  dependent 
to-day,  on  the  sugar  cane  and  the  sugar  beet.  Sugar-producing 
plants  of  lesser  importance  in  commerce  are  the  maple  tree,  the 
date  palm,  the  sorghum  and  the  maize. 

History  of  the  Sugar  Cane. — The  sugar  cane  is  by  far  the  earliest 
plant  from  which  sugar  was  extracted.  Prior  to  its  discovery, 
many  centuries  before  the  Christian  era,  mankind  was  largely 
dependent  upon  honey  as  a  sweetening  agent,  and  the  European 
nations  knew  little  of  its  use  until  the  I3th  and  I4th  centuries. 
The  original  home  of  the  cane  was  undoubtedly  in  the  east,  for 
mention  of  it  is  made  in  many  of  the  sacred  books  of  the  Hin- 
doos and  Chinese.  Its  cultivation  was  gradually  carried  west- 
ward, by  the  Persians  and  Arabs,  and  at  the  time  of  the  cru- 
sades, sugar  factories  were  found  in  operation  in  Syria  and  Pales- 
tine. Carried  still  further  westward  by  the  Saracens  and  Moors, 
it  was  finally  introduced  into  Sicily  and  Spain.  The  discovery 
of  America  shortly  after  this  period  led  the  Spaniards  to  carry 
the  plant  to  the  New  World,  where  it  was  found  that  it  could 
be  successfully  grown  on  the  mainland  and  on  adjacent  islands. 
This  opened  a  new  field  for  the  growth  of  the  cane  and  laid  the 
foundation  of  a  great  industry. 

History  of  the  Sugar  Beet. — The  history  of  the  sugar  beet  in- 
dustry dates  only  as  far  back  as  the  early  days  of  the  iQth  cen- 
tury. A  half  century  before  its  introduction,  the  German  chemist 
Margraff  had  called  the  attention  of  the  Berlin  Academy  of 
Science  to  the  fact,  that  sugar  could  be  extracted  from  the  beet. 
This  discovery,  however,  lay  dormant  until  an  important  histori- 


FOOD   INDUSTRIES  13! 

cal  event  cut  off  the  European  nations  from  their  supply  of  cane 
sugar.  South-western  Europe,  at  that  time,  was  involved  in 
warfare  and  a  great  continental  blockade  was  established  by  the 
English  fleet.  The  nations  of  Europe  deprived  of  cane  sugar 
searched  for  another  supply  to  take  its  place.  Sugar  from  the 
maple  and  glucose  from  the  juice  of  grapes,  were  used  but  could 
not  supply  the  demand.  A  former  pupil  of  Margraff,  Achard, 
finally  turned  the  attention  of  scientists  to  the  beet,  and  a  long 
series  of  investigations  followed  which  had  for  its  final  outcome 
the  birth  of  the  beet  sugar  industry.  It  was  first  established  in 
France  by  a  decree  issued  by  Napoleon,  January  I5th,  1811  and 
was  greatly  fostered  by  him  until  the  disastrous  Russian  cam- 
paign. Although  the  fall  of  that  dynasty  interrupted,  it  did  not 
destroy  the  industry,  and  in  the  course  of  twenty  years  it  had 
become  of  great  commercial  importance.  Undoubtedly,  the  great 
progress  in  this  industry  was  largely  due  to  the  invention  of  the 
polariscope,  which  greatly  assisted  in  a  rapid  determination  of 
the  amount  of  sugar  present  in  the  beet. 

About  this  period  German  scientists  became  interested,  and 
through  their  experimentation,  marked  progress  was  made  in  the 
cultivation  of  the  beet  and  in  the  methods  of  manufacture,  which 
in  time  placed  Germany  at  the  head  of  the  sugar  producing  coun- 
tries of  the  world.  While  the  beet  sugar  industry  has  reached 
its  highest  development  in  Germany,  it  is  rapidly  becoming  an 
important  source  of  sugar  in  the  United  States. 

Comparison  of  Cane  and  Beet  Sugar. — Since  the  time  that  beet 
sugar  began  to  assume  commercial  importance,  there  has  been 
much  discussion  in  regard  to  the  relative  merits  of  these  sugars, 
for  use  in  the  household.  Scientists  claim  that  chemically  they  are 
the  same,  both  having  the  formula  C^H^O^,  yet  it  has  often 
been  said  that  beet  sugar  is  not  as  sweet  as  cane  sugar,  and  that 
it  cannot  be  used  successfully  for  canning,  jelly-making  and  pre- 
serving. Experiments  along  this  line  were  carried  on  at  the  Cali- 
fornia Experiment  Station  by  Prof.  G.  W.  Shaw.  The  con- 
clusion drawn  from  his  experimental  data  was  that  sugar  derived 
from  these  two  sources  give  equally  satisfactory  results,  both  in 


132  FOOD   INDUSTRIES 

the  household  and  for  commercial  purposes.  Any  differences 
occurring  seemed  due  rather  to  processes  of  manufacture  such  as 
degree  of  fineness  in  granulation,  rather  than  to  the  composition 
of  the  sugars. 

Properties  of  Sugar. — From  the  manufacturer's  standpoint, 
there  are  three  important  properties  to  be  considered  in  preparing 
the  raw  material  for  the  market;  1st,  solubility  in  water;  2nd, 
crystallization;  3rd,  production  of  invert  sugar. 

THE  CANE  SUGAR  INDUSTRY. 

The  manufacture  of  cane  sugar  as  a  rule  is  divided  into  two 
distinct  industries:  ist,  the  plantation  where  the  plant  is  grown, 
the  juice  extracted  and  made  into  raw  sugar,  the  form  in  which 
it  is  exported ;  2nd,  the  refinery  where  the  raw  sugar  is  received, 
impurities  removed  and  the  sugar  recrystallized,  in  which  form 
it  is  placed  upon  the  market. 

At  the  Plantation. — GROWTH. — The  sugar  cane  belongs  to  the 
family  of  grasses.  It  can  be  grown  in  a  variety  of  climates,  but 
thrives  best  where  it  is  moist  and  warm  with  intervals  of  hot,  dry 
weather.  Such  conditions  are  found  near  the  coast  in  tropical 
and  sub-tropical  countries.  Cuba,  Hawaii,  Porto  Rico,  the  Philip- 
pine Islands,  all  raise  the  sugar  cane  extensively.  In  the  United 
States  this  industry  is  confined  to  the  Gulf  States  especially 
Texas  and  Louisiana. 

OUTLINE  OF  THE  PRODUCTION  OF  RAW  SUGAR. — 
I.  Cane  cut  in  the  green  stage. 

,   (  begasse. 
II.  Cane  crushed  j  crude  juice 

,   f  woody  fiber. 

III.  Crude  juice  screened  -j  «ujce 

IV.  Juice  treated  with  milk  of  lime;  residue  removed. 
V.  Juice  concentrated. 

a.  Boiled  down  in  open  kettles. 

f  molasses. 
Drained  in  hogsheads  or  casks  }  muscovado  sugar. 

b.  Boiled  down  in  vacuum. 

Separated  in  centrifuge  {  Basses. 
(  raw  sugar. 


FOOD    INDUSTRIES 


133 


Cutting. — The  sugar  cane,  when  the  crop  is  ready,  is  harvested 
by  cutting  the  stalks  as  close  to  the  ground  as  possible.  Consid- 
erable care  must  be  given  that  the  plant  be  cut  at  the  right  time, 
for  should  it  reach  maturity,  much  sugar  would  be  lost  to  the 
manufacturer.  The  sugar  cane  contains  a  substance  known  as 
pectose  which  in  time  changes  to  pectic  acid.  The  presence  of 
this  acid  rapidly  converts  the  sugar  into  invert  sugar  which  is 
not  crystallizable.  The  sugar  planter  knowing  well  the  damage 
this  acid  will  do  to  his  product,  cuts  the  cane  while  it  is  still  green. 


Fig.  32.— Cane  Mill,  Philippines. 
(Courtesy  of  the  School  of  Mines  Quarterly,  Columbia  University.) 

At  the  "green  stage,"  the  plant  contains  the  maximum  amount 
of  sugar  and  the  minimum  of  undesirable  substances.  After 
stripping  the  leaves  from  the  stalk  and  removing  the  green  upper 
portion,  the  Cane  is  taken  to  the  mill  for  the  extraction  of  the 
juice. 

Extraction  of  the  Juice. — The  most  common  method  used  with 
the  cane  is  the  crushing  process  by  means  of  heavy  mills.  The 
cane-mills  of  to-day  are  of  various  types  ranging  from  the  crude 
ox-driven  mill  of  primitive  countries  (Fig.  32)  to  a  high  power 
steam-driven  roller  mill  where  the  most  modern  machinery  can 
be  found.  As  the  cane  is  received  at  the  mill,  it  is  delivered  by 


134 


FOOD    INDUSTRIES 


carriers  to  high  crushers  (Fig.  33),  which  reduce  the  stalks  to  a 
pulpy  fiber  and  extract  much  of  the  juice.  This  mass  then  passes 
to  a  mill  composed  of  three  rollers  of  the  same  size,  set  in  such 
a  way  that  the  first  and  second  are  not  so  close  together  as  the 
second  and  third.  The  rollers  draw  the  cane  within  their  grip, 
subjecting  it  on  its  passage  to  great  pressure,  and  causing  the 
rupture  of  the  cells  and  the  escape  of  more  of  the  juice.  A  second 
and  third  mill  are  sometimes  used,  more  and  more  of  the  juice 
being  extracted  by  each  roll.  It  is  customary  to  spray  the  pulp 


Fig-  33- — Cane  Crusher,  Hawaii. 
(Courtesy  of  the  School  of  Mines  Quarterly,  Columbia  University.) 

as  it  passes  between  the  rolls  to  secure  a  greater  degree  of  ex- 
traction. From  the  roller-mill  two  products  are  obtained,  the 
exhausted  cane  which  is  called  begasse,  and  the  extracted  juice 
which  must  be  purified  before  it  can  be  converted  into  raw 
sugar. 

Even  with  modern  machinery,  the  extraction  of  juice  by  this 
method  is  by  no  means  perfect, — only  from  75  to  80  per  cent,  of 
the  weight  of  cane  in  juice  is  obtained.  As  the  sugar  cane  con- 
tains approximately  88  per  cent,  a  considerable  portion  of  the 
sugar  is  lost  in  the  begasse.  Much  experimenting  has  been  done 


FOOD    INDUSTRIES 


135 


to  remove  the  juice  from  the  cane  by  a  method  which  will  involve 
less  loss.  The  diffusion  method  used  so  largely  in  the  beet  sugar 
industry  has  been  tried,  but  at  present  is  being  used  in  but  few 
of  the  large  plantations  in  the  United  States. 

Purification  of  the  Raiv  Juice. — The  second  important  step  is 
the  purification  of  the  raw  juice  by  straining,  to  remove  bits  of 
cane,  and  the  addition  of  a  clarifying  agent.  Milk  of  lime  is  the 
agent  most  commonly  used  and  the  mass  is  heated  to  boiling. 
This  prevents  fermentation,  neutralizes  the  free  organic  acids 


Fig.  34.— Open  Pan  Evaporators,  Philippines. 
(Courtesy  of  the  School  of  Mines  Quarterly,  Columbia  University.) 


cU 


of  the  juice  and  assists  in  the  coagulation  of  the  dissolved  matter 
A  thick  scum  of  impurities  rises  to  the  top  of  the  kettle.     This 
consists  of  lime  salts  and  albuminous  matter  and  is  known  as 
"the  blanket  scum."     The  impurities  are  removed  by  skimming 
and  by  sedimentation  and  passage  through  a  filter  press. 

Evaporation. — The  concentration  of  the  juice  may  be  carried 
ut  in  two  ways:  ist,  the  old-fashioned  method  of  boiling  down 
in  an  open  kettle ;  2nd,  by  the  use  of  the  vacuum  pan.  Large 
open  pans  or  kettles  usually  made  of  copper  and  heated  over 
direct  fire  are  found  now,  only  in  primitive  countries  or  on  iso- 


10 


136  FOOD    INDUSTRIES 

lated  plantations  (Fig.  34).  Their  use  has  been  found  to  involve 
a  great  loss  of  sugar,  although  the  product  obtained  had  an 
agreeable  aromatic  taste  much  preferable  to  the  refined  sugar  of 
to-day.  It  was  customary  to  boil  down  the  sugar  juice  until  the 
mass  began  to  crystallize.  This  necessitated  a  rise  in  temperature 
from  212°  to  24O°-25o°  F.  and  resulted  in  the  formation  of 
caramel  and  invert  sugar  which  must  be  looked  upon  as  waste, 
from  the  standpoint  of  the  manufacturer.  After  crystallization 
had  reached  the  desired  point,  the  mass  was  freed  from  the  syrup 
by  simply  being  run,  while  hot,  into  hogsheads  having  fine  perfor- 
ated bottoms,  through  which  the  molasses  gradually  drained  out. 


Fig.  35.— Vacuum  Pans,  Hawaii. 
(Courtesy  of  the  School  of  Mines  Quarterly,  Columbia  University.) 

The  light  brown  sugar  obtained  as  a  result  of  this  process  was 
known  as  "muscovado"  sugar.  The  molasses  was  very  dark  in 
color  but  of  excellent  quality  and  without  further  treatment 
could  be  used  as  a  table  syrup. 

In  all  modern  sugar  mills,  evaporation  is  carried  on  in  vacuum 
pans  where  concentration  can  be  brought  about  with  a  lower 
temperature,  i6o°-i8o°  F.,  thus  avoiding  the  losses  always  oc- 
curring in  the  open  kettle  method.  The  vacuum  pan  invented 
in  England  in  1813  is  a  large  closed  vessel  usually  made  of  cop- 
per containing  steam-coils  for  heating,  the  vacuum  being  main- 


FOOD    INDUSTRIES 


137 


tained  by  a  pump  (Fig.  35).  Suitable  openings  are  made  in  the 
side  for  the  entrance  and  exit  of  the  juice,  a  window  is  inserted 
where  the  operation  can  be  watched,  and  an  opening  from  which 
samples  can  be  taken  and  tested.  When  the  vacuum  pan  was 
first  introduced  into  this  industry  only  one  was  used.  It  has 
been  found  of  great  economic  value,  however,  to  use  the  vacuum 
evaporators  in  series  of  two,  three  or  more,  known  as  the  mul- 
tiple effect  vacuum  (Fig.  36).  When  arranged  in  series,  a  low 


Fig.  36.— Multiple-effect  Evaporating  Apparatus. 

vacuum  is  maintained  in  the  first  vessel,  a  little  higher  in  the 
second  and  still  higher  in  the  third  and  so  on.  The  boiling  point 
for  each  succeeding  vessel  is  thus  reduced.  When  the  system  is 
in  operation,  the  steam  arising  from  the  juice  in  the  first  vessel 
passes  to  the  coils  of  the  second  vessel  and  serves  as  a  heating 
agent.  The  steam  from  the  juice  of  the  second  vessel  in  turn 
serves  as  a  heating  medium  for  the  third  vessel.  After  the 
clarified  juice  has  been  evaporated  to  a  syrup,  it  is  run  into  a 
single  vacuum  pan  known  as  "the  strike  pan"  when  a  high  degree 


138  FOOD    INDUSTRIES 

of  vacuum  is  maintained  (Fig.  37).  There  it  is  concentrated 
until  the  sugar  begins  to  grain.  Crystallization  is  allowed  to 
continue  until  the  pan  is  full  of  crystals  the  desired  size.  The 


-  37- — Vacuum  Strike  Pan. 


mixture  of  crystals  and  syrup  is  known  as  "massecuite."  The 
vacuum  is  then  broken,  air  is  admitted  and  the  bottom  of  the 
pan  is  opened  so  the  contents  can  be  transferred  to  a  mixing  ap- 
paratus where  the  massecuite  is  kept  in  gentle  motion.  While 


FOOD    INDUSTRIES 


139 


still  warm,  the  mixture  is  passed  to  a  centrifugal  machine  which 
causes  a  separation  of  the  crystallized  sugar  and  the  molasses. 

Centrifugal. — The  centrifugal  or  centrifuge  is  a  hollow  iron 
drum  containing  a  perforated  basket  (Fig.  38).  It  can  be  rapidly 
rotated  during  which  the  sugar  mass  is  thrown  against  the  sides 
of  the  basket  and  the  molasses  passes  through  the  perforations. 
The  sugar  is  then  bagged  and  shipped  to  the  country  where  it  is 
to  be  refined. 


Fig.  38.— Centrifugal  Machines.     (Courtesy  of  Sugar,  Chicago,  111.) 

This  is  known  as  "the  first  sugar"  and  the  molasses  drained 
from  the  sugar  is  called  "the  first  molasses."  This  molasses  may 
be  sold  for  household  use  or  as  it  contains  much  sugar,  it  may 
be  again  worked  over.  This  is  accomplished  by  boiling  it  down 
in  vacuum  and  again  centrifuging.  By  this  means  a  second 
sugar  and  a  second  molasses  are  obtained.  The  second  molasses 
may  again  be  boiled  down  for  a  third  sugar  and  molasses.  While 


140 


FOOD    INDUSTRIES 


the  third  molasses  still  contains  about  30  per  cent,  sugar,  it  con- 
tains so  many  impurities  that  the  sugar  will  not  crystallize  out. 

THE  BEET  SUGAR  INDUSTRY. 
GROWTH. — Unlike  the  cane,  the  sugar  beet  reaches  its  highest 


Fig-  39.— The  Wild  Beet.     (Courtesy  of  Sugar,  Chicago,  111.) 

development  in  a  north  temperate  climate,  although  where  the 
soil  has  exceptionally  good  qualities,  it  has  been  grown  success- 


FOOD    INDUSTRIES 


141 


fully  in  sub-tropical  regions.     It  is  not  apt,  however,  to  contain 
as  much  sugar.     Moisture  also  plays  an  important  part  in  the 


Fig.  40. — The  Sugar  Beet  of  To-day.     (Courtesy  of  Sugar,  Chicago,  111.) 

>roduction  of  a  normal  crop.  The  sandy  soil,  temperature,  and 
loisture  near  our  western  rivers  in  Colorado,  and  neighboring 
>tates,  furnish  satisfactory  farm  land  for  this  industry.  Beets 


142 


FOOD    INDUSTRIES 


FOOD   INDUSTRIES  143 

can  also  be  grown  successfully  in  irrigated  areas  and  much  waste 
land,  it  is  hoped,  may  be  utilized  in  this  way.  Much  experiment- 
ing is  being  done  in  regard  to  the  cultivation  of  the  beet,  and 
.great  improvement  has  been  made  especially  in  increasing  the 
sugar  content  (Figs.  39  and  40).  The  average  percentage  of  the 
sugar  is  13-14  per  cent.,  while  on  the  irrigated  area  it  has  been 
increased  to  16-18  per  cent.  The  yield  per  acre  is  still  low, 
however,  not  exceeding  eight  tons,  while  in  Europe  twelve  to 
thirteen  tons  are  obtained  (Fig.  41). 

OUTLINE  OF  THE  PRODUCTION  OF  RAW  SUGAR.  — 
I.  Beets  are  grown,  harvested,  topped. 
II.   Washed. 

III.  Sliced. 

IV.  Diffused 

V.  Crude  juice  is  screened. 
VI.  Defecated. 

VII    Filtered  {  all?uminous  matter,  etc. 

(  juice. 
VIII.   Concentrated  in  vacuum. 

IX. 


Topped.  —  After  harvesting,  it  is  necessary  to  remove  the  tops 
with  a  small  part  of  the  neck  of  the  beet.  The  object  of  remov- 
ing this  portion  is  to  prevent  the  large  accumulation  of  mineral 
matter  at  the  top  from  entering  the  factory,  as  it  interferes  with 
the  crystallization  of  the  sugar.  This  work  is  done  in  Europe 
as  a  rule  by  women  and  children.  In  the  United  States,  foreign 
labor  is  gradually  replacing  the  custom  of  sending  whole  families 
into  the  field  during  the  harvesting  season. 

Washing.  —  On  entering  the  factory,  the  beets  are  first  washed 
to  remove  adhering  soil,  sand  and  pebbles.  This  work  is  accom- 
plished in  long  troughs,  each  containing  a  revolving  shaft  which 
carries  pins  set  in  the  form  of  a  screw.  These  push  the  beets 
along  the  trough  against  a  stream  of  water,  and  the  rubbing 
against  one  another  loosens  the  dirt,  which  is  carried  away  by 
the  water. 


144 


FOOD    INDUSTRIES 


Extraction  of  the  Juice. — In  considering  the  method  of  extrac- 
tion of  the  juice  from  the  beet,  the  composition  plays  an  impor- 
tant part.  In  the  beginning  of  this  industry,  the  crushing  process 
was  used  similar  to  that  employed  with  the  sugar  cane,  but  was 
found  so  unsatisfactory  that  it  has  been  almost  entirely  replaced 
by  the  diffusion  process. 


Composition  of  the 
sugar  cane 

Composition  of  the 
sugar  beet 

Water  • 

7C     8c          v 

Fiber  etc 

°7    /5/0 

75  °5      x 

A     ft 

4  ° 

u»3    |BV> 

n  Q     y    c 

•\5   z*o 

Wax   fat   etc  

O  A 

A  comparison  of  these  two  important  sugar  yielding  materials 
will  reveal  marked  differences  in  composition,  which  make  neces- 
sary the  employment  of  different  processes,  for  the  extraction  of 
the  sugar.  The  cane  which  contains  a  relatively  large  proportion 
of  fibrous  material  yields  very  readily  to  crushing  by  rollers, 
while  the  beet  containing  more  water  and  less  fiber  is  reduced 
to  a  pulpy  mass  very  difficult  to  handle.  It  may. also  be  noted 
that  the  beet  contains  more  nitrogenous  and  mineral  matter  and 
less  invert  sugar  than  the  cane. 

Slicing. — In  order  to  obtain  the  best  results  with  the  diffusion 
method,  the  beets  are  sliced  into  thin  pieces  by  a  machine  con- 
taining revolving  knives.  These  slices  are  known  as  chips  in 
English,  corsettes  in  French  and  schnitzel  in  German. 

The  chips  after  being  weighed  are  run  into  vessels  in  which  a 
current  of  warm  water  displaces  the  juice  in  the  beet  by  the 
process  of  osmosis.  Foreign  matter  which  is  colloidal  cannot 
pass  through  the  cell  walls  of  the  beet;  the  sugar  being  crystal- 
line, however,  passes  out  into  the  water. 

The  Diffusion  Battery. — The  vessels  in  which  the  sugar  is 
extracted  are  known  as  diffusion  batteries  (Fig.  42).  They 
are  usually  arranged  in  a  series  of  10-12  upright  iron  cylinders 


FOOD   INDUSTRIES  145 

called  cells  which  are  connected  by  pipes,  the  outlet  from  the  top 
of  one  cell  passing  downward  into  the  bottom  of  the  next,  and 
so  on  through  the  entire  series.  The  cells  can  be  placed  in  a 
row  or  in  a  circular  position. 

When  ready  for  operation,  the  chips  are  fed  by  means  of  a 
swinging  trough  into  the  cells  through  a  manhole  at  the  top,  and 
warm  water  about  140°  F.  is  passed  through  the  system.  The 


Fig.  42.— The  Circular  Diffusion  Battery.     (Courtesy  of  Sugar,  Chicago,  111.) 

circulating  liquid  remains  about  twenty  minutes  in  each  cell, 
removes  sugar  from  the  beet  chips  and  is  passed  to  the  next  cell. 
Heaters  or  "juice  warmers"  are  placed  between  the  cells  to  again 
raise  the  liquid  to  the  desired  temperature.  As  the  juice  passes 
from  battery  to  battery,  it  grows  stronger  in  sugar  content.  When 
it  has  become  sufficiently  concentrated  it  is  sent  to  the  defecating 
>om  and  fresh  water  is  passed  through  the  batteries.  The 
>rocess  is  continued  until  practically  all  the  sugar  has  been  re- 


146  FOOD   INDUSTRIES 

moved  from  the  beet  chips.     There  is  rarely  more  than  0.5  per 
cent,  loss  of  sugar  with  this  method  of  extraction. 

During  the  sugar  season,  the  battery  is  constantly  in  use.  Being 
arranged  in  series,  it  is  possible  to  circulate  liquid  through  from 
8  to  10  cells  while  two  are  being  emptied  and  refilled  with  fresh 
chips. 

Clarification  of  the  Juice. — The  sugar  solution  known  as  "the 
diffusion  juice"  is  almost  as  black  as  ink  as  it  comes  from  the 
batteries,  and  must,  therefore,  be  clarified.  This  is  usually  accom- 
plished by  adding  an  excess  of  lime,  heating,  and  treating  with 
CO2.  The  lime  is  converted  into  the  carbonate  form  and  in  pre- 
cipitating carries  down  much  of  the  impurities  which  are  re- 
moved by  a  filter  press.  The  process  is  usually  repeated  two  or 
three  times  or  until  the  liquid  is  clear.  The  first  carbonation  is 
stopped  when  the  greater  part  of  the  lime  has  been  precipitated, 
but  while  there  is  still  about  o.i  per  cent,  of  lime  in  solution. 
The  impurities  precipitated  with  the  carbonate  of  lime  are  insol- 
uble in  an  alkaline  solution,  but  redissolve  in  a  neutral  solution. 
After  the  first  carbonation,  the  juice  is  filter-pressed  to  remove 
the  precipitated  carbonate  of  lime  and  impurities,  and  then  car- 
bonated a  second  time  to  precipitate  most  of  the  remaining  lime, 
this  time  to  an  alkalinity  of  0.02  or  0.03  per  cent.  The  second 
filtration  is  usually  through  gravity  filters  where  only  a  very 
gentle  pressure  is  applied. 

The  clear  juice  is  then  concentrated  in  vacuum  and  separated 
by  the  centrifuge  into  molasses  and  raw  beet  sugar,  the  processes 
being  similar  to  those  used  for  cane  sugar. 

Raw  beet  sugar  contains  substances  of  decidedly  unpleasant 
odor  and  taste,  due  to  nitrogenous  matter  and  mineral  salts  being 
taken  up  from  the  soil  by  the  roots  of  the  beet.  It  must,  there- 
fore, always  be  refined  even  when  modern  machinery  and  up-to- 
date  methods  have  been  used.  The  molasses  obtained  can  be 
worked  over  until  most  of  the  sucrose  has  been  obtained.  It  is 
very  impure,  however,  from  mineral  salts  and  nitrogenous  com- 
pounds, which  give  it  so  disagreeable  an  odor  and  taste  that  it 
is  never  fit  for  table  use. 


FOOD   INDUSTRIES  147 

REFINING  OF  RAW  SUGAR. 

Raw  sugars,  with  the  exception  of  maple,  are  now  refined 
before  being  placed  upon  the  market.  The  refining  of  sugar  was 
not  practiced  until  about  500  A.  D.  It  first  appeared  in  Mesopo- 
tamia and  gradually  traveled  westward,  refineries  being  erected 
in  many  of  the  European  countries  in  the  I5th  and  i6th  cen- 
turies. In  1689  the  first  refinery  of  the  Western  Continent  was 
built  in  New  York  City.  This  industry  has  gradually  grown 
until  public  taste  now  demands  a  pure  white  sugar.  As  before 
stated,  so  far  as  the  beet  sugar  is  concerned,  refining  is  a  neces- 
sity since  the  raw  product  has  a  disagreeable  odor  and  taste. 
Cane  sugar,  however,  possesses  in  the  raw  state  a  more  fragrant 
odor  and  agreeable  taste  than  in  the  refined  product. 

Refining  sugar  is  in  theory  a  simpler  process  than  the  prepara- 
tion of  the  raw  product,  but  it  requires  great  care  and  attention 
to  details.  Experience  has  shown  that  it  can  only  be  done  eco- 
nomically in  very  large  establishments,  which  are  usually  located 
on  a  navigable  river,  where  the  cargoes  can  be  readily  received 
and  unloaded.  Refineries  are  built  many  stories  high  so  as  to 
take  advantage  of  gravity  in  passing  the  solution  from  one 
process  to  another.  An  abundant  water  supply  is  also  a  necessity. 

The  process  consists  essentially  in  dissolving  the  crude  material, 
separating  the  impurities  and  recrystallizing  the  sugar. 

OUTUNE  OF  THE  REFINING  PROCESS. — 
I.   Raw  sugar  washed. 

II.  Centrifuged{^esdy™P- 

III.  Washed  raw  sugar  melted. 

IV.  Defecated. 


V.  Filtered  through  bags  j  j™^*0' 


VI.   Liquor  bone-blacked. 
VII.  Boiled  down  in  vacuum. 

,  (  syrup. 

VIII.  Centrifuged  |  ®^P    {  yellow  sugar. 


Washing. — The  raw  sugar  after  being  weighed  is  mixed  with 


148 


FOOD    INDUSTRIES 


a  low  grade  sugar  solution.  This  process  assists  in  removing 
soluble  impurities. 

From  the  mixing  tank,  the  magma  of  raw  sugar  and  syrup  is 
fed  into  a  centrifuge  which  is  rapidly  rotated.  The  purified  raw 
sugar  remains  on  the  sides  of  the  basket  and  the  syrup  containing 
most  of  the  coloring  matter,  dirt,  glucose  and  gum  passes  through 
the  perforations.  The  purified  raw  sugar  is  left  99-99^  per 
cent.  pure. 

The  Melter. — The  washed  raw  sugar  is  dissolved  in  a  melting 
tank,  which  contains  steam  coils  and  a  revolving  arm  for  stirring. 
When  the  density  of  the  liquid  is  about  30°  Be.,  it  is  pumped  into 
defecators  or  "blow-ups." 


Fig.  43. — Filter  Bags. 

Defecators. — Here  the  solution  is  treated  for  the  removal 
of  such  impurities  as  organic  acid  and  fine  suspended  matter. 
Different  clarifying  agents  can  be  employed,  such  as  alum  or 
blood  albumin.  To  a  large  extent  now  a  treatment  with  calcium 
acid  phosphate  or  phosphoric  acid  and  milk  of  lime  is  used.  The 
mixture  is  heated  and  agitated  for  about  twenty  minutes.  Soon 
a  flocculent  precipitate  separates  out,  carrying  with  it  suspended 
matter  and  some  of  the  coloring. 

Filtration. — The  impurities  are  removed  by  a  mechanical  filtra- 
tion through  cotton-twill  bags  enclosed  in  coarse,  strong  netting 
sheaths.  They  are  6-7  feet  long  and  5-6  inches  in  diameter.  The 


FOOD   INDUSTRIES  149 

open  end  is  tied  tightly  around  a  metallic  nipple  by  which  the 
bag  is  suspended  (Fig.  43).  The  first  run  of  liquor  is  often 
muddy  and  must  be  refiltered.  When  the  filter  bags  have  become 
exhausted,  they  are  rinsed  in  several  waters.  The  mud  washed 
out  contains  about  20  per  cent,  of  sugar,  part  of  which  can  be 
recovered. 

Bone-black  Filters. — These  filters  are  large  cylindrical  iron 
tanks  filled  with  bone-black,  a  material  obtained  by  the  charring 
of  bones  and  reducing  them  to  a  granular  form  by  a  crushing 
process.  Bone-black  has  the  power  of  decolorizing.  About  one 
pound  is  used  to  one  pound  of  sugar.  In  passing  through  these 
filters,  the  sugar  solution  loses  most  of  its  color,  a  small  amount 
of  ash  and  organic  impurities.  It  is  collected  in  storage  tanks  ac- 
cording to  its  color  and  purity.  The  char  in  time  loses  its  power 
of  removing  color,  and  must  be  revivified.  It  is  washed,  drained, 
dried,  put  in  a  kiln  and  highly  heated  to  expel  organic  impurities. 

Vacuum  Pan. — The  decolorized  sugar  solution  passes  to  the 
vacuum  pan  and  is  then  boiled  to  grain. 

Centrifugal. — After  cooling,  the  separation  of  the  sugar  and 
syrup  is  accomplished  by  means  of  centrifugal  force.  At  this 
stage,  blue  water  is  sometimes  used  to  give  a  white  appearance 
to  the  sugar. 

The  sugar  is  dried  and  passed  through  screens  to  separate  it 
into  grades.  It  is  bagged  or  barreled  to  appear  on  the  market 
as  granulated  sugar. 

Block  sugar  may  be  made  in  two  ways. 

I.  The  boiled  mass  from  the  vacuum  pan  containing  syrup 
and  crystals  of  sugar  may  be  drained  into  conical  moulds  and 
allowed  to  stand  for  about  two  weeks.  It  is  occasionally  washed 
by  means  of  a  pure  sugar  solution.  The  uncrystallized  sugar 
slowly  drains  off  through  a  small  hole  opened  at  the  p<jint  of 
the  cone.  The  dried  sugar  is  then  cut  into  cubes.  A  modified 
form  of  this  process,  which  greatly  shortens  the  time,  is  now 
being  used  in  Europe  and  to  a  slight  extent  in  America.  By 
centrifugal  force,  the  cones  can  be  freed  in  a  few  minutes  from 
the  syrup,  and  the  sugar  after  drying  can  be  cut  into  blocks. 


I5O  FOOD   INDUSTRIES 

II.  Granulated  sugar  while  still  moist  can  be  pressed  into 
blocks  by  an  ingenious  machine,  and  gently  dried  in  an  oven. 

Powdered  Sugar. — Granulated  sugar  can  be  reduced  to  a  pow- 
der. When  very  finely  ground  it  is  placed  upon  the  market  as 
confectioner's  sugar. 

Sugars  are  coarse  grain  or  fine  grain  according  to  the  length 
of  time  allowed  in  crystallizing.  When  the  operation  is  slow, 
the  crystals  are  large;  rapid  crystallization  yields  small  crystals. 

Yellow  Sugar. — The  syrup  obtained  as  one  of  the  final  products 
in  the  refining  process,  contains  much  sugar  and  can  be  worked 
over  for  a  second  sugar  and  second  syrup.  Sugar  obtained  by 
the  treatment  of  syrups  usually  appears  on  the  market  as  light 
brown  sugar;  darker  colors  are  largely  low  grade  sugars. 

Utilization  of  the  By-Products. — Wherever  primitive  methods 
for  the  extraction  of  cane  sugar  are  used,  little  thought  is  given 
to  the  by-products.  This  is  not  true,  however,  in  progressive 
countries  where  modern  machinery  and  methods  are  employed. 
Under  such  conditions,  the  utilization  of  waste  matter  is  being 
carefully  considered.  Such  material  is  obtained  as  follows:  1st, 
refuse  of  the  beet  and  cane;  2nd,  impurities  removed  in  the  clari- 
fying processes ;  3rd,  molasses.  The  beet  tops  make  an  excellent 
food  for  cattle.  They  may  be  dried  by  the  sun  or  with  mechan- 
ical means  or  they  may  be  converted  into  ensilage.  The  beet 
pulp  remaining  in  the  diffusion  batteries,  may  also  be  utilized 
as  cattle  food  in  the  form  of  wet  pulp  where  it  can  be  used  im- 
mediately, in  the  dried  state,  or  after  conversion  into  ensilage. 
In  the  cane  sugar  industry,  the  leafy  portion  of  the  cane  top  is 
fed  to  animals,  while  the  begasse  has  been  utilized  mainly,  in 
the  past,  for  fuel  purposes.  In  recent  years,  it  has  been  discov- 
ered that  an  excellent  quality  of  paper  may  be  manufactured 
from  begasse.  While  very  little  is  being  done  along  that  line  at 
present,  the  development  of  paper  manufacture  in  connection 
with  this  industry,  may  prove  of  great  importance. 

In  both  the  cane  and  beet  sugar  industry,  the  filter  cakes  ob- 
tained during  the  clarifying  processes  are  rich  in  mineral  matter, 
and  may  be  successfully  used  as  fertilizer. 


i 


FOOD   INDUSTRIES  151 

Molasses  constitutes  the  most  valuable  by-product  As  it 
contains  a  large  percentage  of  sugar  which  cannot  be  crystallized 
out  with  ordinary  methods,  chemical  means  are  being  devised 
for  its  extraction.  Beet  sugar  molasses  contains  50  per  cent, 
of  sucrose.  By  treatment  with  calcium,  strontium  or  barium 
hydroxides,  it  is  possible  to  precipitate  the  sucrose  as  insoluble 
saccharate  which,  after  filtration,  may  be  decomposed  and  re- 
covered as  sucrose.  Beet  sugar  molasses  being  rich  in  nitro- 
genous and  mineral  constituents  may  be  utilized  for  fertilizing 
material  with  certain  kinds  of  soil.  It  is  also  useful  as  a  cattle 
food  and  for  fuel  purposes. 

Molasses  from  the  cane  industry,  may  be  used  as  a  table  syrup 
or  for  feeding  cattle,  after  being  mixed  with  begasse  or  such 
material  as  bran  meal  or  similar  products.  In  both  the  beet  and 
cane  sugar  industries,  the  molasses  is  used  largely  for  the  manu- 
facture of  rum  and  alcohol.  Lesser  products  obtained  through 
fermentation  of  cane  sugar  molasses  are  acetic,  butyric,  capry- 
lic  and  other  fatty  acids.  Many  valuable  by-products  of  a  nit- 
rogenous nature  may  also  be  obtained  from  beet  sugar  molasses. 
Maple  Sugar. — A  sugar  and  syrup  highly  prized  for  confec- 
tionery and  table  use  can  be  obtained  from  the  maple  tree.  In 
the  United  States,  they  are  made  almost  entirely  in  Vermont, 
New  York,  Ohio  and  Indiana.  The  process  is  comparatively 
simple.  In  the  spring,  when  the  sap  begins  to  run,  the  trees  are 
bored  and  the  sap  escapes  into  receptacles.  It  is  usually  evap- 
orated in  open  kettles  and  allowed  to  crystallize.  The  sugar  is 
sold  in  the  raw  state,  as  the  delicate  flavor  so  much  desired  is 
ost  in  refining  processes. 

Date  Palm  Sugar. — In  India,  the  date  palm  yields  a  low  grade 
crude  sugar  known  as  "jaggary."  Much  of  this  sugar  is  shipped 
to  England  for  refining. 

Sorghum. — The  sorghum  cane  belongs  to  a  family  of  grasses 

resembling  the  sugar  cane.     It  has  been  known  and  valued  in 

China  for  many  centuries.     Many  attempts  have  been  made  in 

his  country  in  recent  years  to  extract  sugar  from  the  sorghum, 

ut  without  great  success.     The  juice  contains   dextrin  bodies 

ii 


152  FOOD   INDUSTRIES 

which  prevent  crystallization  of  part  of  the  sugar.  It  is  used 
largely,  however,  for  the  production  of  syrup.  The  stalks  can 
be  utilized  for  the  manufacture  of  coarse  wrapping  paper  and 
the  seeds  for  fodder. 

Cane  Syrup. — Cane  syrup  is  prepared  largely  in  small  mills  in 
our  own  Southern  States  by  the  use  of  primitive  methods.  The 
juice  of  the  sugar  cane  is  extracted,  clarified,  partly  inverted  and 
evaporated  until  25-30  per  cent,  of  the  water  remains,  which  is 
sufficient  to  prevent  the  crystallization  of  the  sugar. 

Adulteration  of  Sugar. — With  the  exception  of  pulverized  sugar 
very  little  has  been  found  in  the  United  States  on  account  of 
the  cheapness  of  the  product.  Sugar  sold  in  the  powdered  form, 
however,  has  been  adulterated  from  time  to  time  with  flour, 
glucose,  chalk,  silica  and  gypsum. 


CHAPTER  XL 


ALCOHOLIC  BEVERAGES. 

Alcoholic  beverages  may  be  classified  as  follows: 

f  Beer. 
I.   Malted  fermented       \ 

L  Stout. 

II.   Malted  distilled          ^  Whiskey. 
Sweet  or  dry. 

I  Red'  Claret»  Burgundy,  etc. 
(  White,  Sauterra,  Rhine,  etc. 
C  Still,  most  of  the  natural  wines. 

III.  Wines  ^  3.   CO.,          -j  Sparkling,  Champagne  and  Sparkling 

(_      Moselle. 

(  Natural,    containing   not   more   than 
|  4.  Alcohol  •<       15%.     Most  of  the  natural  wines. 
(.  Fortified,  Sherry,  Port  and  Maderia. 

IV.  Distilled  Wines  <|  Brandy. 
V.   Cordials,  liqueurs  and  Gin. 

VI.  Sophisticated  Wines. 

Historical. — The  use  of  alcoholic  beverages  dates  back  to  the 
earliest  historic  times ;  hardly  a  race  of  men  is  known  even 
among  savage  tribes  which  has  not  its  fermented  drink.  The 
process  of  beer  brewing  is  of  great  antiquity,  but  undoubtedly 
that  of  wine  making  is  of  still  earlier  origin.  It  may  well  be 
imagined  that  primitive  man  stumbled  upon  this  process  by  acci- 
dent. A  vessel  containing  crushed  fruit  juice,  set  aside  for 
future  use,  may  have  been  found  to  contain  a  drink  far  more 
exhilarating  than  the  ordinary  fresh  fruit  juice.  Early  we  find 
that  in  all  countries  where  fruit  could  .be  readily  grown,  a  fer- 
mented drink  of  this  kind  was  used.  Through  this  simple  art 
of  wine  making,  aided  by  the  development  of  human  intelligence, 
the  discovery  was  finally  made  of  how  a  fermentable  sugar  could 
be  obtained  by  the  treatment  of  a  grain.  From  that  time  fer- 
mented grains  were  used,  during  seasons  when  fruit  could  not 
be  obtained,  and  in  regions  not  adapted  to  the  growing  of  fruit. 
The  art  of  beer  making  must  have  been  discovered  in  early  times, 


154  FOOD   INDUSTRIES 

for  references  are  made  to  the  beverage  in  Egyptian  records 
dating  back  to  3000  B.  C.  It  is  related  that  an  attempt  was  made 
by  their  government  to  suppress  beer-shops  over  forty  centuries 
ago.  The  Egyptians  taught  the  ancient  Greeks  and  Romans  the 
art  of  brewing,  and  beer  was  used  as  a  beverage  by  the  soldiers 
of  Caesar's  army.  Latin  authors  show  that  the  drink  was  in 
their  time  extensively  used  in  Western  Europe.  The  Saxons 
became  accustomed  to  its  use  before  they  settled  in  Britain,  and 
for  centuries  it  was  used  as  the  national  beverage  by  all  English 
people. 

Beer  was  prepared  from  barley,  which  could  be  readily  grown 
in  the  British  Isles,  and  was  indulged  in  at  every  meal  by  men, 
women  and  children.  A  housewife  was  judged  as  much  by  her 
skill  in  brewing  as  by  the  bread  that  she  baked.  Families  became 
noted  for  making  exceptionally  fine  beer  and  recipes  were  handed 
down  in  verbal  form,  from  parent  to  child,  and  the  secret  most 
carefully  guarded.  Beer  being  a  common  drink  of  most  of  the 
European  people  before  the  establishment  of  the  colonies  in 
America,  it  followed  naturally  that  the  early  settlers  brought 
with  them  to  the  New  World  the  art  of  brewing. 

Fermentation. — For  the  production  of  alcoholic  beverages,  the 
manufacturer  is  as  dependent  upon  the  yeast  plant  as  the  maker 
of  bread.  The  baker  desires  carbon  dioxide  only,  while  the 
brewer  needs  for  his  product,  alcohol  principally  and,  in  some 
beverages,  carbon  dioxide  also. 

Even  under  the  most  favorable  conditions,  there  is  a  limit  to 
the  amount  of  alcohol  that  yeast  can  produce.  When  the  alco- 
holic strength  reaches  14-15  per  cent.,  yeast  can  no  longer  propa- 
gate itself  and  fermentation  ceases.  Conditions  for  its  growth, 
such  as  temperature,  food,  oxygen  and  moisture,  have  been  care- 
fully studied  in  connection  with  this  industry,  and  modern  scien- 
tific research  has  placed  at  the  disposal  of  the  brewer  of  to-day, 
a  wealth  of  knowledge  which  was  not  known  to  his  predecessors. 
Most  conspicuous  among  the  scientists  who  made  investigations 
along  these  lines  was  Louis  Pasteur,  the  father  of  modern  bac- 
teriology. It  was  from  the  study  of  the  phenomena  of  brewing 


' 


FOOD    INDUSTRIES  155 

that  he  finally  gave  to  the  world  the  theories  of  fermentation. 
The  study  of  brewing  has  contributed  much  to  science,  for 
research  work  has  also  been  done  along  the  lines  of:  ist, 
processes  of  germination  in  seeds ;  2nd,  the  chemistry  of  car- 
bohydrates and  protein  compounds;  3rd,  the  action  of  micro- 
organisms and  enzymes. 

Yeast  for  the  brewer's  purpose  is  divided  into  two  groups, 
namely,  top  yeast  and  bottom  yeast.  For  its  growth  top  yeast 
requires  rather  a  high  temperature — 60° -80°  F.  Fermentation 
is  very  active;  the  rapid  evolution  of  CO2  causes  the  liquid  to 
bubble  violently,  and  as  the  CO2  escapes  to  the  surface  much  of 
the  yeast  is  carried  to  the  top  of  the  vat.  This  type  of  yeast  is 
used  for  heavy  ales  and  beers,  for  alcohol,  whiskey  and  high 
wines.  Bottom  yeast  acts  at  a  lower  temperature — 4O°-5o°  F. 
Fermentation  is  very  slow,  the  evolution  of  CO2  is  gradual  and 
the  yeast  remains  on  the  bottom  of  the  vat. 

In  fermenting  at  a  high  temperature  yeast  generally  dies.  At 
a  low  temperature,  it  can  be  kept  for  a  considerable  time  and  can 
sometimes  be  used  as  a  starter  for  the  fermentation  of  the  next 
liquid.  Above  86°  F.,  the  alcoholic  fermentation  readily  passes 
into  the  butyric  and  other  forms  of  decomposition.  It  is  also 
subject  to  the  lactic  and  acetic  ferments.  Much  study  has  been 
given  to  the  temperature  of  fermenting  beer. 

Temperature  for  growth : 

Yeast 32°-i2o°  F. 

Lactic  ferment    5o°-i3o°  F. 

Acetic  ferment 5o°-i22°  F. 

With  these  facts  in  mind  the  brewer  on  the  continent  and  in 
America  uses  a  low  temperature,  possibly  48°-5o°  F.  This 
allows  the  growth  of  yeast  and  prevents  the  development  of 
lactic  and  acetic  ferments. 

THE  BREWING  OF  BEER. 

Raw  Material. — For  the  manufacture  of  beer,  water,  yeast, 
hops  and  a  malted  grain  are  necessary.  The  water  should  be 
free  from  organic  impurities  and  in  general  should  be  moderately 
hard.  Continental  brewers  use  a  soft  water,  but  in  England  and 


156  FOOD   INDUSTRIES 

America,  the  presence  of  gypsum  is  preferred.  Water  contain- 
ing sodium  chloride,  calcium  and  magnesium  sulphates  has  been 
found  to  be  very  Satisfactory.  A  soft  water  has  a  greater  solvent 
power  on  protein,  which  is  likely  to  undergo  decomposition. 
Hops  are  the  catkins  of  the  hop  plant.  They  contain  several 
bitter  principles  which  give  a  desirable  flavor  to  beer.  Hops 
also  act  as  an  antiseptic.  In  the  early  days  of  brewing,  beer  was 
always  prepared  from  wheat  and  barley;  later  oats,  millet  and 
anise  were  sometimes  substituted.  At  the  present  time,  barley 
stands  foremost  among  the  cereals  used  in  this  industry,  on 
account  of  its  flavor  and  yield  of  diastase.  Rye  also  occupies  a 
prominent  position  and  in  Russia  and  Austria  wheat  is  still 
largely  used.  In  some  parts  of  the  United  States,  corn  under  the 
name  of  grits  plays  an  important  part,  while  rice  is  used  largely 
in  the  Orient  and  by  American  brewers.  In  Germany,  beer  is 
often  prepared  from  potatoes. 
Processes  in  the  Manufacture  of  Beer. — 
{  i.  Steeping. 

I.  Malting   j   £   ?™£tinl' 

I  4.   Drying. 
II.  Preparation  of  the  wort. 

III.  Boiling 

IV.  Cooling 

V.  Fermentation. 

VI.  Preservation 

Malting. — In  the  classification  of  the  carbohydrates,  we  find  the 
disaccharid  maltose  C12H22O1:l.  This  substance  is  never  found 
in  nature,  in  large  amounts,  .as  is  sucrose  and  lactose,  but  must 
always  be  prepared  by  allowing  the  enzyme  diastase  to  act  upon 
starch.  Here  by  the  process  of  hydrolysis,  starch  passes  through 
the  dextrin  stages  to  maltose.  Maltose  is,  therefore,  a  partially 
digested  carbohydrate  and  since  much  of  it  occurs  in  beer,  that 
beverage  contains  material  of  food  value,  as  well  as  stimulating 
principles. 

Except  in  very  large  breweries,  malting  is  now  generally 
done  by  a  separate  industry.  This  process  of  changing  barley 


FOOD    INDUSTRIES  157 

into  malt  is  divided  into  four  stages :  steeping,  couching,  flooring 
and  drying.  When  the  barley  is  received  at  the  malting  house, 
dust,  dirt,  broken  kernels  and  foreign  seeds  must  first  be  removed. 
This  is  accomplished  by  revolving  sieves  and  strong  currents  of 
air.  It  is  now  ready  for  the  processes  of  malting,  during  which 
period,  the  production  of  diastase  is  the  chief  aim  of  the  maltster. 
The  mode  of  formation  is  not  yet  known  but  it  occurs  during  the 
sprouting  of  the  grain. 

In  order  to  soften  the  grain,  it  is  soaked  in  water  in  large 
wooden  vats  for  two  or  three  days,  fresh  water  being  added 
from  time  to  time.  During  this  period  any  imperfect  grains 
remaining,  will  float  and  can  easily  be  removed  by  skimming; 
perfect  grains  gradually  sink.  This  process  is  stopped  when  the 
grains  have  softened  so  the  skin  can  easily  be  removed.  A  test  is 
usually  made  by  piercing  the  grain  with  a  needle.  By  this  time, 
the  grain  should  have  absorbed  sufficient  moisture  to  allow 
germination  to  begin  so  the  water  is  drawn  off.  The  swollen, 
softened  grain  is  couched  by  being  piled  in  heaps  about  24  inches 
deep,  on  a  cement  floor,  in  rooms  moderately  light.  The  tem- 
perature is  very  important,  about  60°  F.  is  maintained,  as  a.  high 
degree  often  causes  mold  growth.  In  the  olden  times,  it  was 
necessary  to  carry  on  this  process  in  the  spring  and  autumn. 
Now  malting  plants  are  artificially  controlled  in  temperature, 
so  couching  can  be  carried  on  in  any  part  of  the  year.  The  grain 
is  kept  moist  by  a  frequent  sprinkling  with  water,  a  good  cir- 
culation of  air  is  maintained  to  supply  sufficient  oxygen,  and  it 
is  turned  from  time  to  time.  It  gradually  begins  to  "sweat," 
the  temperature  rises,  and  an  agreeable  odor  is  given  off.  At  the 
end  of  twenty-four  to  thirty-six  hours,  tiny  rootlets  have  ap- 
peared and  sprouting  has  begun. 

By  means  of  wooden  shovels  it  is  next  spread  out  on  the  floor 
in  layers  of  about  10  inches.  This  is  called  flooring.  To  pre- 
vent its  heating  too  rapidly,  every  few  hours  it  is  turned  over  so 
new  grains  are  exposed;  frequent  sprinkling  keeps  it  moist. 
From  six  to  twelve  days,  the  tiny  rootlet  called  "the  acrospire" 
is  allowed  to  grow.  During  this  time,  two  important  ferments, 


158 


FOOD    INDUSTRIES 


diastase  and  peptase,  have  been  formed.  The  production  of 
diastase  increases  as  germination  proceeds  until  it  reaches  a  maxi- 
mum, then  it  begins  to  decrease.  It  is  at  the  maximum  stage 
when  the  sprout  has  grown  three-quarters  of  the  grain.  The  pro- 


Fig.  44.— Roller  Mill  for  Grinding  Barley  Malt.    (Courtesy  of  United  States 
Brewers'  Association.) 

cess  is  then  stopped.  As  soon  as  the  diastase  is  formed  it  begins 
to  act  on  the  starch  of  the  barley,  gradually  changing  part  of  it 
to  dextrin  and  maltose. 

Germination  is  stopped  by  drying..    This  may  be  accomplished 


FOOD    INDUSTRIES 


159 


by  air-drying  or  in  a  kiln.  The  character  and  odor  of  the  beer 
are  much  influenced  by  the  method  of  drying.  A  low  tempera- 
ture produces  a  pale  malt,  higher  heat  gives  yellow,  amber  and 
brown.  After  drying,  the  rootlets  are  brittle  and  can  easily  be 
removed  by  passing  the  grain  through  sieves  containing  rotary 
brushes.  The  grain  is  now  called  barley-malt. 

The    Wort. — The   preparation    of   the   wort    or   the   mashing 
process  is  the  second  stage  in  the  making  of  beer.     The  malt  is 


Fig.  45.— Filter  Presses  for  Clarifying  the  Wort.     (Courtesy  of  United  States 
Brewers'  Association.) 

cleaned  and  coarsely  ground  in  a  roller  mill  (Fig.  44),  and  a 
water  extract  is  made.  Another  cereal  such  as  corn  or  rice  may 
be  added.  This  process  is  intended  not  only  to  extract  the  dex- 
trin and  maltose  already  formed,  but  to  allow  the  diastase  to 
act  upon  any  starch  present  so  it  may  be  converted  into  dextrin 
and  maltose.  Peptase  is  also  active,  converting  protein  matter 
to  the  more  easily  digested  form  of  peptone.  Great  care  is  given 


i6o 


FOOD   INDUSTRIES 


that  the  temperature  be  kept  at  the  point  where  the  diastase  and 
peptase  can  do  the  most  effective  work.  Tests  are  made  from 
time  to  time  with  iodine.  After  a  certain  length  of  time  the 
watery  extract  is  drawn  off  and  fresh  water  is  added.  This  is 
called  the  second  extract.  Again  a  third  extract  may  be  made. 
These  extracts  when  mixed  are  passed  through  a  filter  press 
(Fig.  45).  They  are  known  as  the  wort.  The  wort  contains 
dissolved  material  which  has  been  acted  upon  by  ferments. 


Fig.  46.— Copper  Boilers.     (Courtesy  of  United  States  Brewers'  Association.) 

Boiling. — The  wort  is  run  into  copper  kettles  where  it  is  boiled 
from  one  to  two  hours  (Fig.  46).  Hops  are  added  during  this 
time.  The  boiling  accomplishes  several  desirable  changes:  1st, 
Unchanged  protein  coagulates  and  separates  out.  This  change 
is  assisted  by  tannic  acid  dissolved  from  hops.  2nd,  The  wort 
is  concentrated  and  sterilized.  3rd,  The  constituents  of  hops 
are  taken  up  by  the  wort.  They  give  taste,  aroma  and  keeping 
quality  to  beer. 


FOOD   INDUSTRIES  l6l 

Cooling. — After  boiling,  the  temperature  must  be  dropped 
rapidly  to  prevent  undesirable  fermentation  from  starting.  This 
is  accomplished  by  running  the  boiling  hot  liquid  into  cooling 
tanks,  then  passing  it  quickly  over  pipes  through  which  brine  is 
being  circulated.  It  is  cooled  down  to  a  temperature  of  40°  F., 
the  point  needed  for  the  fermentation  by  yeast. 

Fermentation. — For  a  long  period,  fermentation  of  the  wort 
took  place  in  great  open  vats  made  of  oak  It  was  left  for  spon- 
taneous fermentation  or  more  often  yeast  was  added.  Recent 
experimentation  has  proved  that  fermentation  is  far  more  satis- 
factory when  carried  on  in  closed  iron  vats  lined  with  porcelain, 
through  which  filtered  air  is  forced.  In  the  use  of  the  closed  re- 
ceptacle, pure  yeast  cultures  may  be  utilized  with  great  efficiency. 
As  bottom  fermentation  is  used  in  America,  the  temperature  is 
kept  below  50°  F.  This  method  produces  less  alcohol  but  the 
flavor  of  the  beer  is  considered  better.  In  England,  top  fer- 
mentation is  more  popular.  It  requires  a  higher  temperature, 
65°-8o°  F.,  the  action  is  rapid  and  more  alcohol  is  developed.- 

I.  Main  fermentation  lasts  from  4-8  days,  when  a  high  tem- 
perature is  used;  and  from  9-10  days  in  bottom  fermentation. 
During  this  period,  new  yeast  cells  are  constantly  forming  and 
in  their  desire  for  food  are  breaking  down  sugars  into  alcohol, 
carbon  dioxide,  glycerine  and  succinic  acid.     As  the  action  goes 
on,  there  is  a  tendency  for  the  temperature  to  rise.     It  was  cus- 
tomary in  olden  time  to  float  in  the  vats,  cans  containing  ice. 
As  most  modern  breweries  have  a  cooling  plant,  brine  is  circulated 
through  coils  in  the  bottom  of  the  vats.     By  these  means  the 
desired  temperature  can  be  maintained.     At  the  end  of  this  pro- 
'Cess,  it  is  called  the  "new  beer." 

II.  For  the  after  fermentation  the  new  beer  is  drawn  from 
the  vats  into  casks  containing  beech  wood  shavings,  which  have 
been  passed  through  a  sterilizing  process.     Isinglass  can  also  be 
used.     These  assist  in  clarifying  the  beer.     The  temperature  is 
kept  low,  the  yeast  cells  gradually  cease  growing  and  in  settling, 
become  attached  to  the  shavings,  leaving  the  beer  clear. 

III.  The  storage  fermentation  takes  place  in  casks  and  lasts 


1 62 


FOOD    INDUSTRIES 


from  three  to  six  months.  During  this  time  flavor  is  developed. 
Fresh  beer  is  added  to  give  the  product  its  head  and  fermentation 
goes  on  slowly  at  a  low  temperature,  after  which  the  beer  is  ready 
to  be  filtered  and  bottled  or  barreled  (Fig.  47). 

Preservation. — Pasteurization  is  sometimes  used  and  is  a  per- 
fectly legitimate  method  of  preserving  beer.  The  temperature 
is  raised  to  140°  F.,  which  is  high  enough  to  kill  any  ferment 
present. 


Fig.  47. — Filter  Presses  for  Clarifying  Beer  before  Bottling.      (Courtesy  of 
United  States  Brewers'  Association.) 

Great  care  must  be  given  to  the  bottling  and  barreling  process. 
The  barrels  are  usually  coated  on  the  inside  with  pitch  and  are 
regularly  inspected.  They  may  be  disinfected  with  SO2  or  thor- 
oughly sterilized  with  live  steam  and  rinsed  with  filtered  water. 

Any  carelessness  at  this  stage  causes  the  souring  of  beer.  The 
keeping  qualities  depend  on  absolute  cleanliness  in  barreling  or 


FOOD   INDUSTRIES  163 

bottling,  purity  of  the  water  and  yeast,  and  the  quality  of  the 
grain  and  hops.  Sanitary  conditions  should  be  maintained 
throughout  brewing. 

The  use  of  preservatives  such  as  silicylic  acid  or  boracic  acid, 
is  forbidden  by  many  countries. 

Composition  of  Beer. — Beer  contains  when  ready  for  use  dex- 
trins,  maltose,  peptones,  alcohol  3-7^  per  cent.,  and  carbon  di- 
oxide. The  addition  of  hops  gives  tannin,  volatile  oils  which 
give  a  better  flavor,  alkaloids  which  have  a  narcotic  effect,  and 
resins  which  contain  antiseptic  principles  and  protect  against 
undesirable  fermentation.  Bitter  substances  have  been  added  to 
give  pungency,  as  quassia,  gentian  root  and  ginger,  but  their  use 
is  now  prohibited  by  most  governments. 

Adulteration. — The  adulteration  of  beer  is  of  early  origin.  In 
1620  mention  is  made  that  cocculas  indicus  was  used  in  Holland 
and  during  the  reign  of  Queen  Anne,  of  England,  it  was  necessary 
for  Parliament  to  pass  a  law  prohibiting  brewers  from  using 
this  substance,  as  well  as  other  unwholesome  ingredients.  One  of 
the  earliest  books  written  on  food  adulteration,  exposes  the  prac- 
tices of  the  brewers  of  the  early  igth  century.  Such  substances 
as  ground  alum,  coloring  matter,  beans,  quassia,  capsicum,  cara- 
way seeds,  grains  of  Paradise,  strychnine  and  picric  acid  were 
frequently  used.  Beer  many  times  was  prepared  from  chemical 
preparations,  substituted  for  malt  and  hops. 

While  much  has  been  said  against  the  brewer  of  modern  times, 
it  is  safe  to  say  that  adulteration  has  practically  disappeared  in 
this  industry.  There  is  a  prevailing  belief  that  beer  contains  a 
variety  of  substances  such  as  opium,  belladonna,  strychnine  and 
corrosive  acids,  but  these  ideas  are  not  true.  The  only  harmful 
ingredients  are  preservatives.  Sodium  bicarbonate  is  sometimes 
used  to  overcome  acidity  and  to  increase  the  head. 

Substitution. — Beer  is  generally  supposed  to  be  made  from 
barley  malt.  This  operation  is  long  and  involves  a  certain 
amount  of  waste  so  is  expensive.  Brewers  sometimes  substitute 
glucose.  This  is  practically  the  same  practice  that  is  found  in 


164 


FOOD   INDUSTRIES 


malted  breakfast  foods.  It  is  not;  however,  injurious  if  the 
glucose  is  a  pure  article. 

Kinds  of  Beer. — Lager  beer  is  used  in  Germany  and  to  a  great 
extent  in  America.  It  is  always  made  by  bottom  fermentation, 
where  the  process  is  allowed  to  proceed  slowly  and  has,  therefore, 
less  alcohol,  but  a  more  desirable  flavor  and  better  keeping  qual- 
ities. Lager  means  stored,  so  this  variety  of  beer  is  always  stored 
six  months.  It  is  brewed  in  the  winter  and  stored  until  the  fol- 
lowing summer.  There  is  usually  the  addition  of  a  large  amount 
of  hops. 

Ale  is  a  light  colored  beer  made  by  top  fermentation.  It  has, 
therefore,  more  alcohol,  about  7^2  per  cent.  The  bitter  flavor  is 
due  to  the  addition  of  more  hops  than  in  ordinary  beer.  It  is 
practically  the  only  beer  made  in  England,  as  they  use  top  fer- 
mentation. 

Porter  is  a  dark  colored  beer.  When  a  high  temperature  is 
used  in  kiln-drying  malt,  the  carbohydrates  present  become  par- 
tially charred  and  caramel  is  formed.  This  gives  color  and  flavor 
to  the  beer.  Porter  contains  about  5  per  cent,  alcohol. 

Stout  is  a  porter  with  a  higher  percentage  of  alcohol  usually 
about  7  per  cent.  It  contains  more  of  the  extracts. 


CHAPTER  XII. 


ALCOHOLIC  BEVERAGES.     (Continued.) 


THE  WINE  INDUSTRY. 

Wine  is  the  fermented  juice  of  a  fruit  which  contains  sugar 
or  its  derivative  invert  sugar.  While  any  sweet  fruit  may  be 
used,  the  term  wine  generally  refers  to  the  juice  of  the  grape, 
for  that  is  the  only  fruit  which  is  cultivated  on  an  extensive 
scale  for  the  manufacture  of  wine.  Grapes  owe  their  wine  pro- 
ducing value  to  several  important  constituents:  1st,  the  large 
amount  of  grape  sugar  which  often  constitutes  18-20  per  cent, 
of  the  weight  of  the  fresh  fruit  and  more  than  half  of  the  solid 
matter;  2nd,  the  organic  acids  of  which  tartaric  is  the  most  im- 
portant; 3rd,  the  proteins  which  greatly  influence  fermentation. 

The  cultivation  of  the  grape  for  this  purpose  began  in  the 
Orient,  and  gradually  extended  into  the  middle  and  south  of 
Europe,  and  into  the  northern  part  of  Africa  along  the  countries 
bordering  on  the  Mediterranean.  France,  Spain  and  Portugal  are 
now  the  chief  wine  producing  countries  of  Europe,  although 
along  the  banks  of  the  Rhine  and  Moselle  Rivers  as  well  as  other 
parts  of  Germany,  Austria  and  Italy,  grapes  are  cultivated  in 
large  quantities.  The  islands  of  the  Atlantic  and  certain  sections 
of  America,  as  California,  New  York,  Ohio  and  Virginia,  are  also 
important  wine  manufacturing  centers.  The  climatic  conditions 
and  the  character  of  the  soil  greatly  influence  the  quality  of  the 
grape.  The  vine  grows  on  soil  containing  mineral  matter,  chalk, 
magnesia  and  silica.  It  appears  to  thrive  best  along  the  borders 
of  rivers  and  on  ground  which  can  attract  considerable  moisture 
from  the  subsoil.  The  composition  varies  from  season  to  season 
due  to  weather  conditions.  A  warm  summer  with  a  moderate 
amount  of  rain  gives  the  highest  percentage  of  sugar  and  tar- 
taric acid.  During-  a  cold,  rainy,  grape  growing  season,  less 
sugar  is  produced  and  a  higher  percentage  of  malic  acid  is 
developed. 

The  varieties  are  very  numerous  and  there  is  great  difference 


1 66  FOOD   INDUSTRIES 

in  the  cultivation  in  various  localities,  but  wherever  grapes  are 
grown  for  the  wine  industry,  great  care  and  experience  are 
absolutely  essential. 

Processes  in  the  Manufacture  of  Still  Wine. — 

I.  Grapes  picked  when  fully  ripe. 
II.  Crushed  between  rolls  or  with  the  feet. 

III.  Pressed  or  centrifuged. 

C  Active. 

IV.  Fermentation  j  Still. 

(  Storage. 

Picking. — Grapes  are  taken  for  wine  making  either  when  ripe 
or  slightly  over  ripe,  according  to  the  character  of  the  wine. 
The  harvesting  usually  begins  early  in  September  and  continues 
into  November.  The  early  grapes  usually  contain  the  largest 
amount  of  sugar,  but  those  taken  later  in  the  season  when  al- 
lowed to  become  over  ripe,  produce  a  wine  having  a  peculiar 
bouquet  which  is  much  prized. 

The  grapes  are  picked  by  hand  or  with  a  fork.  Except  in 
certain  districts,  the  common  practice  is  to  gather  all  the  grapes 
carried  by  the  vine  and  to  sort  them  into  grades.  The  care  given 
in  sorting,  differs  greatly  according  to  the  quality  of  the  wine. 
For  the  finest  wines,  all  unripe,  bruised,  sun-burned  and  rotten 
grapes  are  discarded.  In  the  manufacture  of  red  wine,  the  stems 
are  also  removed  by  causing  the  grapes  to  pass  through  a  series 
of  sieves  by  which  the  stems  are  retained.  The  almost  universal 
practice  in  white  wines  is  to  allow  the  grapes  to  remain  upon  the 
stems  during  the  pressing,  as  the  separation  of  the  must  and 
marc  takes  place  before  the  astringent  principle  which  they  con- 
tain can  be  communicated  to  the  must. 

Extraction  of  the  Juice. — In  order  to  extract  the  juice,  the 
grapes  must  first  be  softened.  This  may  be  accomplished  by 
treading  underfoot  in  vats  or  by  crushing  between  grooved  roll- 
ers, great  care  being  taken  that  the  pressure  be  gentle,  so  that 
the  juice  from  the  pulp  only  will  be  extracted.  Heavy  pressure 
forces  the  juice  from  the  skins  and  bruises  the  seeds  and  stems  if 
these  have  not  been  removed.  This  greatly  injures  the  flavor 


FOOD  INDUSTRIES  167 

of  the  wine.  Treading  with  the  feet  has  probably  been  the  most 
satisfactory  method.  Wooden  shoes  are  now  worn  as  they  are 
more  sanitary  and  give  a  gentle  even  pressure.  The  softened 
grapes  are  pressed  or  passed  through  a  centrifugal  machine.  At 
this  stage,  for  white  wines,  the  skins  are  removed  if  the  blue 
grapes  are  being  used.  If  red  wine  is  wanted,  the  skins  are  left 
on.  After  pressing  or  centrifuging,  the  juice  is  known  as  the 
"must"  and  the  pulp  and  skins  as  the  "marc."  The  quality  of 
the  wine  depends  on  the  "must."  The  first  portion  is  often  col- 
lected separately  as  it  is  the  juice  of  the  ripest  and  sweetest 
grapes.  That  which  is  pressed  from  the  grapes  later  contains 
more  acid  and  tannin,  for  it  is  obtained  from  the  unripe  grapes 
and  skins. 

Fermentation. — The  fermentation  of  red  wines  usually  takes 
place  in  large  open  vats  of  wood,  marble  or  stone.  White  wines 
are  generally  fermented  in  barrels  with  only  the  bungholes  opened 
for  the  escape  of  the  carbon  dioxide  generated.  Although  the 
use  of  yeast  cultures  has  recently  been  introduced  in  certain 
localities,  fermentation  is  still  almost  always  spontaneous  in  the 
wine  industry.  Spores  of  the  wild  yeast  are  always  present  on 
the  skins  of  grapes  and  in  the  air  of  grape  producing  regions,  so 
fermentation  begins  at  once.  A  temperature  of  about  50°  F. 
is  maintained  for  bottom  fermentation  and  70°  F.  if  top  fer- 
mentation is  desired. 

Fermentation  is  divided  into  three  stages. 

I.  Main  fermentation. — During  this  period  the  yeast  cells  are 
very  active,  the  liquid  becomes  turbid,  carbon  dioxide  is  given 
off,  a  scum  forms  and  a  sour  taste  and  odor  are  developed.     Tt 
lasts  from  one  to  three  weeks  according  to  the  temperature  used. 
When  fermentation   is  completed,   the  evolution  of   gas  ceases, 
yeast  cells  and  other  suspended  matter  settle  to  the  bottom  and 
the  liquid  becomes  clear.     During  this  process  the  proteins  are 
largely  consumed  by  the  yeast. 

II.  Still  Fermentation. — The  new  wine  is  run  into  tungs  or 
casks  where  it  remains  until  the  following  spring.     During  this 
after  fermentation  the  young  wine  slowly  loses  its   sugar  and 

12 


1 68  FOOD    INDUSTRIES 

remaining  protein  substances.  Acid  potassium  tartrate  and  cal- 
cium tartrate  separate  out  and  form  deposits  known  as  argol  and 
lees.  For  further  information  see  Chapter  VIII,  Leavening 
Agents. 

III.  Storage  Fermentation. — The  storage  of  wine  lasts  for 
many  years  according  to  the  quality.  Very  rich  wines  are  held 
for  eight  years  or  more,  cheaper  varieties  from  two  to  four.  Dur- 
ing this  process  of  ripening  the  desired  bouquet  is  gradually  de- 
veloped. This  is  due  to  the  formation  of  etheral  salts,  from  the 
alcohols  and  organic  acids  present  in  the  wine.  Minute  quanti- 
ties of  higher  alcohols  known  as  fusel  oil  are  developed  during 
fermentation.  As  they  are  of  a  poisonous  nature,  the  formation 
of  these  salts  not  only  means  the  development  of  desirable  fla- 
vors but  the  lessening  of  the  toxic  quality  of  the  wine.  Tannins 
and  other  impurities  are  gradually  precipitated.  Sometimes  dur- 
ing the  ripening  process  clarifying  agents  such  as  gelatin  and 
albumin  are  added  to  assist  in  dragging  down  suspended  mat- 
ter. The  treatment  with  gelatin  is  particularly  applied  to  sweet 
and  heavy  white  wines  which  frequently  remain  more  or  less 
turbid.  Albumin  as  a  rule  is  used  with  red  wines  which  contain 
tannic  acid. 

Improving1  Wines. — The  juice  pressed  from  the  grape  varies 
in  composition  to  a  considerable  extent  from  year  to  year,  ac- 
cording to  the  amount  of  rain  fall,  sunshine  and  temperature. 
As  a  result  it  is  usually  treated  or  improved  in  some  way  to 
maintain  certain  proportions.  The  must  of  a  poor  season  can 
be  so  treated  as  to  bring  it  up  to  the  standard  of  a  must  of  a 
good  year,  by  correcting  the  ratio  of  acid  to  sugar.  Any  excess 
of  acidity  may  be  overcome  by  neutralizing  with  marble-dust  and 
the  addition  of  a  certain  quantity  of  cane  sugar.  To  improve 
the  sweet  taste  without  injuring  the  keeping  qualities  glycerine 
is  sometimes  added.  Wine  deficient  in  alcohol  and  containing 
a  large  amount  of  acid  is  frequently  improved,  by  the  addition  of 
wine  of  a  succeeding  year.  The  practice  of  adding  gypsum  or 
plaster  of  Paris  has  prevailed  extensively  in  the  countries  of 
south  and  south-western  Europe.  This  is  known  as  "plastering," 


I  ; 

t 


FOOD   INDUSTRIES  169 

and  is  supposed  to  have  for  its  object  the  withdrawal  of  a  cer- 
tain amount  of  water  from  the  must,  thus  increasing  the  alcoholic 
strength.  It  also  deepens  the  color  and  adds  to  the  keeping 
qualities.  Public  opinion  is  strongly  against  the  custom,  how- 
ever, as  it  is  supposed  to  have  an  injurious  effect  on  the  con- 
sumer of  the  wine.  The  process  is  now  controlled  by  law. 

In  certain  heavy  wines  as  Port  and  Madeira,  alcohol  is  added 
and  they  are  known  as  fortified  wines.  The  amount  of  alcohol 
developed  during  fermentation  never  exceeds  12-13  Per  cent- 
Alcohol  is  added  to  fortified  wines  until  the  strength  reaches 
16-22  per  cent. 

CHAMPAGNE. 

The  art  of  making  champagne  was  discovered  by  a  monk  dur- 
ing the  1 8th  century.  Both  white  and  red  grapes  are  used  and 
a  special  treatment  is  necessary.  Great  care  is  given  in  picking  so 
that  the  grapes  are  not  crushed,  or  coloring  matter  may  be  added 
to  the  juice.  The  branches  are  detached  one  by  one  and  care- 
fully sorted  according  to  their  ripeness.  In  some  localities  even 
the  individual  grape  is  examined.  After  picking  they  are  crushed 
quickly  in  order  to  prevent  any  coloring  matter  being  taken  up. 
The  first  press  only  is  used  for  champagne,  the  second  and  third 
being  utilized  for  cheaper  wines.  After  the  must  has  been  al- 
lowed to  stand  long  enough  for  impurities  to  settle,  it  is  run  im- 
mediately into  casks  for  the  main  fermentation,  which  usually 
takes  place  in  cool  cellars.  The  young  wine  is  allowed  to  fer- 
ment until  the  early  winter,  when  it  is  cleared  with  isinglass  and 
racked  off  into  other  casks.  At  the  end  of  one  month  this  opera- 
tion is  repeated.  Before  bottling  it  is  mixed  with  a  certain 
proportion  of  old  wine  and  cane  sugar.  The  bottles  are  then 
placed  in  a  horizontal  position  in  champagne  vaults,  where  they 
remain  six  months  or  longer.  New  fermentation  starts,  much 
CO2  is  developed  and  a  quantity  of  sediment  is  formed.  This 
scum  can  later  be  removed  by  first  placing  the  bottles  in  an 
inclined  position  so  impurities  will  gather  near  the  cork,  which  is 
hen  carefully  removed  just  long  enough  to  allow  the  sediment 
to  be  blown  off.  By  chilling  the  bottles  just  before  the  opera- 


I7O  FOOD  .INDUSTRIES 

tion,  the  pressure  is  reduced  and  the  cork  can  be  liberated  with 
very  little  trouble.  The  loss  in  the  bottle  is  replaced  quickly  by 
sugar,  fine  wine  and  aromatic  essences,  and  the  bottle  is  again 
corked  and  wired.  Champagne  is  usually  held  for  a  period  in 
order  to  allow  blending  and  ripening  to  take  place  before  it  is 
placed  upon  the  market. 

An  imitation  champagne  is  sometimes  made  by  forcing  carbon 
dioxide  into  a  sweet  white  wine  to  which  liqueur  has  been  added. 

Sophisticated  Wines. — The  so-called  sophisticated  wines  are 
prepared  by  mixing  water,  alcohol,  tannin,  sugar,  tartaric  acid, 
fruit  essences  and  the  like,  closely  imitating  the  composition  of  a 
regularly  fermented  wine. 

Composition  of  Wine. — Wine  contains  water,  alcohol,  glycerine, 
ethereal  salts,  and  other  volatile  prodilcts  giving  flavor  and 
bouquet,  grape  sugar,  tartaric  and  malic  acids,  mineral  matter, 
pectin,  gummy  matter  and  tannin. 

Adulteration. — The  practice  of  adulterating  wine  is  almost  as 
old  as  the  wine  industry.  The  ancient  Greeks  and  Romans  were 
forced  to  pass  strict  laws  to  prevent  such  practices,  and  officials 
were  appointed  to  detect  and  punish  those  who  adulterated  wine. 
Substitution  and  adulteration  are  still  being  carried  on  exten- 
sively. Innumerable  substances  have  been  added — water,  glyc- 
erine to  give  sweetness,  coloring  agents  such  as  berries,  beets,  coal 
tar  products  and  holly-hocks,  flavoring  to  make  inferior  wines 
appear  older  and  better  grade,  cloves,  bitter  almonds  and  elder- 
berry juice.  In  France,  on  account  of  the  failure  of  the  wine 
crop  in  recent  years,  a  wine  has  been  made  from  dried  raisins 
and  prunes  and  substituted  as  grape  wine.  Raisin  and  prune 
wine  is  a  perfectly  legitimate  product  only  when  sold  under  its 
own  name. 

By-Products. — Cheap  wines  are  prepared  by  adding  water  and 
sugar  to  the  marc  and  fermenting  it.  This  wine  is  largely  used 
by  the  poorer  people  on  the  continent.  The  marc  may  also  be 
utilized  in  the  production  of  cheap  brandy  and  vinegar,  as  a  fer- 
tilizer, for  fuel  purposes  and  for  cattle  food. 

In  Europe  tannic  acid  is  extracted.    This  is  used  extensively  in 


FOOD    INDUSTRIES  \J\ 

the  textile  industry.  The  preparation  of  cream  of  tartar  from 
argol  is  another  important  industry  connected  with  wine  making. 
Preservation. — Pasteurizing  and  the  use  of  preservatives  are 
practiced  in  this  industry  similar  to  the  processes  described  under 
beer  making. 

DISTILLED   LIQUORS. 

Distilled  liquors  differ  from  malted  beverages  such  as  beer, 
ale,  porter  and  stout,  and  from  products  of  the  wine  industry, 
in  two  important  ways : 

I.  In  the  fermentation  process,  every  effort  is  made  to  have  a 
maximum  amount  of  alcohol  developed. 

II.  The  fermented  liquid  is  distilled  and  redistilled  in  order 
to  have  a  product  rich  in  alcohol. 

There  are  three  classes  of  distilled  liquors. 

I.  BRANDY. — The  first  class  of  distilled  liquors  uses  as  a  basis 
wine  which  when  distilled  produces  brandy.     The  product  con- 
tains much  of  the  flavor  and  bouquet  of  the  original  wine.     Fic- 
titious brandy  may  be  made  from  grain  or  potatoes,  but  a  true 
brandy  is  always  manufactured  from  the  fermented  juice  of  a 
fruit.     Apples,  peaches,  plums,  cherries  and  blackberries  may  be 
used,  but  by  far  the  largest  amount  is  produced  from  the  grape. 

The  brandy  industry  has  been  chiefly  carried  on  in  France, 
particularly  in  the  southwest  districts,  where  the  product  is 
known  as  cognac.  The  vineyards  in  this  part  of  France  have 
suffered  greatly  in  recent  years  and  the  making  of  imitation 
cognac  is  greatly  increasing. 

A  very  inferior  grade  of  brandy  is  sometimes  made  by  adding 
water  to  the  marc,  fermenting  and  afterward  distilling .  the 
.product. 

II.  RUM. — A   sugar-containing  material   such   as   molasses   is 
always  utilized  in  the  production  of  rum.     This  industry  is  car- 
ried on  very  largely  in  close  proximity  to  sugar  cane  and  sugar 
beet  factories,  which  readily  supply  the  raw  material  in  the  form 
of  molasses  and  sugar  scums.     The  East  Indies  and  the  West 
Indies,  especially  Jamaica,  use  enormous  quantities  of  molasses 
from  the  cane  in  this  way.     In  the  West  Indies,  rum  is  always 


172  FOOD   INDUSTRIES 

flavored  with  caramel.  The  beet  sugar  industry  also  supplies 
much  molasses  for  this  purpose  especially  in  France  and  Ger- 
many. For  the  production  of  rum,  the  sugar-containing  material 
is  diluted,  fermented  and  distilled  until  the  product  contains 
approximately  55  per  cent,  of  alcohol. 

III.  WHISKEY. — In  the  manufacture  of  whiskey  a  starch-con- 
taining material,  for  example  a  cereal,  is  used  as  a  basis.  It  is 
malted,  fermented  and  distilled.  The  cereal  used  as  raw  material 
depends  entirely  upon  the  country.  England  uses  barley,  wheat 
and  oats  and  the  United  States,  corn,  rye  and  barley.  Scotch 
whiskey  is  usually  made  from  malted  barley  which  was  formerly 
dried  in  a  kiln  and  heated  by  glowing  peat.  A  peaty  flavor  was 
imparted  and  retained  by  the  final  product,  which  gave  to  Scotch 
whiskey  a  characteristic  aroma  and  taste  that  were  highly  prized. 
Now,  peat  is  scarcely  used  so  creosote  is  added  to  give  a  similar 
flavor.  In  Russia,  wheat  is  largely  used  giving  a  whiskey  known 
as  "vodka."  Germany  uses  the  potato  almost  exclusively  for  this 
industry. 

Distillation. — In  distilling  these  products,  advantage  is  taken 
of  the  different  boiling  point  of  alcohol  and  water.  At  a  tem- 
perature of  78°-8o°  C.  alcohol  will  volatilize  carrying  with  it 
whatever  is  volatile.  The  still  may  be  very  simple  in  construc- 
tion with  the  same  principle  as  the  water-still  or  it  may  be  very 
complicated.  A  process  known  as  fractional  distillation  is  quite 
extensively  used.  The  hot  vapor  is  chilled  by  coming  in  contact 
with  metallic  diaphragms,  where  a  portion  condenses  and  can  be 
separated  from  the  richly  alcoholic  vapor,  which  passes  on  to 
another  compartment.  The  stills  are  frequently  columnar  in 
shape,  and  are  divided  into  compartments  by  horizontal  copper 
plates,  perforated  with  holes,  and  furnished  with  valves  opening 
upward.  Dropping  pipes  are  attached  to  each  plate,  and  are 
connected  at  their  lower  end  with  shallow  pans.  When  the  still 
is  in  operation,  the  fermented  liquid,  heated  to  the  vapor  state, 
is  allowed  to  enter  the  lowest  compartment.  As  it  rises,  the 
vapor  conies  in  contact  with  a  metallic  diaphragm  which  lowers 
the  temperature,  thus  causing  part  of  the  water  content  to  con- 


FOOD   INDUSTRIES  173 

dense  and  drop  back  through  the  pipe  into  the  shallow  pan.  The 
alcoholic  vapor  passes  on  to  the  compartment  above  where  the 
temperature  is  again  lowered,  causing  more  water  to  condense. 
The  operation  is  continuous  and  can  be  carried  on  until  the  per- 
centage of  alcohol  is  raised  as  high  as  95  per  cent.  This  high 
figure  is  only  used  in  the  production  of  95  per  cent,  alcohol. 
Higher  than  this  can  only  be  obtained  by  chemical  means.  Four 
per  cent,  of  the  water  may  be  removed  by  lime  and  the  remaining 
one  per  cent,  by  metallic  sodium.  The  product  is  then  known  as 
absolute  alcohol.  In  the  distillation  of  fermented  liquids  for 
alcoholic  beverages,  a  strength  of  about  45  per  cent,  is  usually 
obtained,  although  it  may  vary  from  30  to  60  per  cent. 

Bonded  Whiskey. — While  the  chief  constituent  of  whiskey  is 
ethyl  alcohol,  when  freshly  made  it  also  contains  small  quanti- 
ties of  higher  alcohols,  fatty  acids  and  other  volatile  products 
known  as  fusel  oil.  As  these  products  are  considered  injurious, 
whiskey  is  put  in  storage  under  government  protection  for  five 
years.  During  the  process  of  aging,  chemical  changes  take 
place.  Through  oxidation,  ethers  are  formed  from  the  fusel  oil 
which  give  aroma  and  bouquet.  Whiskey  is,  therefore,  improved 
in  two  ways  by  storing:  ist,  it  loses  toxicity;  2nd,  it  gains 
in  flavor.  As  oak  barrels  are  always  used  for  storage,  a  certain 
amount  of  tannin  and  coloring  matter  is  extracted  from  the  oak 
by  the  action  of  the  alcohol. 

CIDER. 

Cider  may  readily  be  regarded  as  a  wine  since  it  is  the  fer- 
mented juice  of  the  apple.  It  is  made  extensively  wherever  that 
fruit  can  be  readily  grown.  Cider  is  manufactured  for  use  as  a 
beverage  and  as  a  foundation  for  what  is  regarded  in  the  United 
States  as  the  best  kind  of  vinegar.  The  fruit  is  chopped  and 
crushed  in  a  mill,  and  the  extracted  juice  is  run  into  barrels,  where 
it  is  allowed  to  ferment.  Where  the  same  care  is  given  as  in  the 
preparation  of  wine  from  grapes,  the  product  is  a  superior  grade 
and  has  good  keeping  qualities.  The  greater  part,  however,  pro- 
duced in  this  country  has  a  very  short  life,  owing  to  the  poor 
quality  of  the  raw  material  and  to  carelessness  in  manufacturing 


174  FOOD   INDUSTRIES 

processes.  The  apples  used  are  often  those  not  marketable  on 
account  of  small  size,  bruises,  greenness  or  decay,  the  perfect 
fruit  as  a  rule  being  used,  only  when  the  crop  is  so  large  that  it 
pays  better  to  make  cider  than  to  sell  the  apples  at  a  low  price. 
Poorly  made  vinegar  is  frequently  adulterated  with  salicylic  acid. 
Cider  is  mildly  alcoholic  in  its  nature,  containing  in  the  sweet 
stage  about  i  per  cent,  and  as  it  ages  from  3  to  5  per  cent, 
alcohol.  In  hard  cider  8  per  cent,  alcohol  is  frequently  found. 
Sugar,  organic  acids  of  which  malic  predominates,  salts  and 
extractives  are  also  present,  the  latter  giving  odor  and  taste. 

VINEGAR. 

Vinegar  is  a  product  obtained  by  the  fermentative  action  of  a 
group  of  bacteria,  on  a  sugary  solution  which  has  undergone 
alcoholic  fermentation,  such  as  cider,  wine,  malted  products  and 
the  like.  The  micro-organisms  cause  the  oxidation  of  the  alcohol 
into  aldehyde  and  ultimately  into  acetic  acid  according  to  the 
following  equation: 

C,H5OH  +  O  — >  CH3CHO  +  H2O, 
CH3CHO  +  O  —  CH3COOH. 

In  this  country  cider  or  wine  vinegars  are  preferred,  while  in 
England  malt  vinegar  is  largely  used.  Until  recent  years,  cider 
vinegar  was  obtained  by  allowing  barrels  partly  filled  with  cider 
to  remain  standing  in  a  warm  cellar  for  a  number  of  months,  the 
bungs  being  left  open.  This  process  was  so  long,  however,  that 
it  has  now  been  almost  entirely  replaced  by  what  is  known  as 
the  "quick  vinegar  process."  Cider  is  allowed  to  percolate  slowly 
through  perforated  casks  filled  with  twigs  or  shavings,  which 
have  been  saturated  with  old  vinegar.  By  this  method  the 
product  is  ready  for  use  in  a  short  time,  but  the  best  varieties 
undergo  a  process  of  aging  before  being  placed  on  the  market. 

In  wine  producing  sections,  vinegar  is  prepared  from  cheaper 
grades  of  wine  and  from  wines  which  have  spoiled  by  the  acetic 
ferment  having  set  in.  White  wine  vinegar  is  usually  consid- 
ered the  best.  It  contains  a  little  more  acetic  acid  than  cider 
vinegar,  also  tartaric  acid  and  some  of  the  mineral  salts  of  the 
grape  as  acid  potassium  tartrate. 


j 


FOOD   INDUSTRIES  1/5 

Cider  vinegar  has  4l/2  to  5^2  per  cent,  acetic  acid  and  marked 
traces  of  malic  acid  which  has  come  from  the  apple.  Mineral 
matter,  sugar  and  extractives  are  also  present,  the  total  solids 
constituting  about  2  per  cent,  of  the  entire  weight. 

As  England  is  neither  a  wine  nor  cider  producing  country,  it 
is  customary  to  make  vinegar  from  a  malted  product  as  the  wort 
of  beer,  the  addition  of  hops  being  omitted  as  they  possess  an 
antiseptic  effect.  Such  a  product  is  dark  in  color  and  has  con- 
siderable extracted  matter  such  as  dextrin,  maltose,  protein,  min- 
eral matter  and  extractives.  The  percentage  of  acetic  acid  is  not 
as  high  as  in  wine  and  cider  vinegar,  therefore,  a  small  amount  of 
sulphuric  acid  is  frequently  added,  o.i  per  cent,  being  allowed 
by  law. 

Vinegar  may  also  be  made  from  sugary  solutions  as  molasses 
or  by  synthetic  processes.  Synthetic  vinegar  is  the  nearest 
approach  to  pure  acetic  acid,  but  as  it  contains  less  dissolved 
material,  it  lacks  flavor. 

Adulteration. — Vinegar  has  been  largely  subject  to  substitution 
and  imitation.  The  best  varieties  on  our  market  are  cider,  wine 
and  malt  vinegar.  Substitution  may  be  detected  by  slowly  evapo- 
rating almost  to  dryness  100  cubic  centimeters  of  vinegar  and 
examining  the  warm  residue.  That  of  cider  vinegar  will  give  a 
distinct  odor  of  baked  apples  and  will  respond  to  the  malic  acid 
test.  The  residue  of  wine  vinegar  contains  tartaric  acid  and  has 
the  aroma  of  the  grape.  Malt  vinegar  gives  a  malt  odor,  distilled 
vinegar  that  of  burnt  sugar,  while  no  residue  on  evaporation 
indicates  a  synthetic  product. 

KOUMISS. 

Koumiss  is  a  fermented  drink  used  largely  in  Russia  and  by 
Asiatic  tribes.  It  was  originally  fermented  mare's  milk,  but  for 
American  purposes  cow's  milk  is  usually  employed.  The  process 
is  started  by  adding  yeast  cultures  and  a  small  amount  of 'sugar 
syrup  to  milk  or  by  mixing  fresh  milk  with  some  already  soured. 
Both  the  lactic  and  alcoholic  fermentation  are  started  and  con- 
tinue for  twenty- four  hours.  The  result  is  a  slightly  sour  milk 
containing  alcohol  and  carbon  dioxide.  It  is  much  used  by 
invalids  and  people  with  weak  digestion. 


CHAPTER  XIII. 


FATS. 

For  information  in  regard  to  the  source,  composition  and 
properties  of  fats,  see  Chapter  I,  Food  Principles. 

Extraction. — The  methods  for  the  extraction  of  fats  differ  ac- 
cording to  the  physical  condition  in  which  they  exist,  their  source 
and  use. 

Animal  fats  are  contained  in  cells  composed  of  membranous 
•tissue,  which  putrifies  soon  after  the  animal  is  killed,  causing  the 
fat  to  become  rancid.  It  must,  therefore,  be  extracted  or  rendered 
immediately  to  prevent  a  foul  odor  from  arising.  Solid  fats  like 
tallow  or  lard  are  freed  from  the  enclosing  membrane  by  finely 
chopping  the  material,  subjecting  to  low  heat  and  drawing  off 
the  fat  in  the  melted  state.  Great  care  is  necessary  that  the 
product  is  not  overheated,  lest  the  neutral  fat  be  decomposed 
into  fatty  acid  and  glycerine.  The  temperature  should  not  exceed 
130°  C.  The  heating  may  be  done  in  open  kettles  over  direct 
flame,  either  with  or  without  the  addition  of  a  small  amount  of 
sulphuric  acid,  or  by  the  action  of  steam  under  pressure. 

The  vegetable  oils  are  found  to  exist  in  largest  quantities  in 
seeds'  and  nuts.  In  order  to  extract  the  oil,  they  are  carefully 
cleaned,  crushed  to  break  the  shell  or  kernel  and  ground  to  a 
fine  powder.  Crushing  is  carried  out  in  machines  called  the  oil 
seed  mill,  some  types  of  which  are  of  great  antiquity.  The  oil 
can  then  be  removed  by  pressure  or  by  the  use  of  a  solvent.  With 
pressure,  heat  may  or  may  not  be  added.  Hot  pressing  gives  a 
larger  yield,  but  a  better  product  is  obtained  with  the  cold 
method.  Many  times  the  cold  process  is  used  first  for  the  extrac- 
tion of  the  highest  quality  oil,  then  heat  is  added  for  lower 
grades. 

A  larger  amount  of  oil  can  be  obtained  by  the  use  of  solvents 
such  as  naphtha,  ether  and  carbon  disulphide,  but  this  method 
cannot  be  used  for  edible  oils. 

Purification. — The  extracted  oils  are  in  a  very  crude  condition, 
containing  suspended  and  dissolved  matter  of  various  kinds  and 


FOOD   INDUSTRIES  1/7 

must  be  purified  even  if  the  oil  is  to  be  used  for  manufacturing 
purposes  such  as  soap-making.  Purifying  can  be  carried  out  by 
filtration  through  cotton-wadding  or  bone-black,  by  the  use  of 
Fuller's  earth,  by  chemical  treatment  or  by  a  bleaching  process. 

BUTTER. 

One  of  the  most  easily  digested  fats  is  butter.  It  has  been 
used  as  a  food  since  the  days  of  the  early  Hebrews,  but  during 
the  Greek  and  Roman  civilization  it  appears  to  have  been  utilized 
only  as  an  ointment. 

The  original  method  of  making  butter  was  very  simple.  Whole 
milk  was  put  in  a  bag  prepared  from  animal  skins  and  the  mass 
was  agitated  until  the  butter  appeared.  This  involved  a  great 
amount  of  labor  and  a  considerable  loss  of  fat,  so  in  time  the 
separation  out  of  the  fat  by  the  method  known  as  creaming  came 
into  use. 

Composition  of  Butter.  — 

Water  ...    12  —  16%  f  Butyrin. 

i.  Soluble  10%     \  Caproin. 
I  Caprylin. 

Fat  .....  .    82.5+  </<  1  LCaprin' 

fOlein. 
t  2.   Insoluble  90%  -j  Palmitin. 

(  Stearin. 
Protein  ........  trace  <j  Caseinogen. 

Carbohydrate  .  .  trace  <j  L,actose. 

Mineral  matter  ............ 


The  object  in  butter  making  is  to  extract  from  milk  its  fat, 
which  exists  in  an  emulsified  form.  The  United  States  Standard 
butter  requires  at  least  82.5  per  cent,  fat  and  not  more  than 
16  per  cent,  water.  The  fat  consists  largely  of  palmitin,  .olein 
and  a  small  amount  of  stearin,  mixed,  not  chemically  combined, 
in  about  the  same  proportion  as  found  in  lard.  In  addition 
to  these  non-volatile  fats,  there  exists  in  small  amounts,  various 
volatile  fats  which  give  to  butter  its  'characteristic  taste  and 
aroma.  The  most  important  are  butyrin,  caproin,  caprylin,  and 
caprin. 


178 


FOOD    INDUSTRIES 


Processes  in  Butter  Making.— 


fl.  Gravity  f  Shallow  pan. 
J  (  Deep  setting  j 


system. 

I.  Separation  of  the  cream 

i 

^  2.   Centrifugal  force. 

II.  Ripening  of  the  cream. 

III.  Churning. 

IV.  Washing. 
V.  Working. 

Separation  of  the  Cream. — The  separation  of  fat  from  milk. 
from  the  earliest  times  to  comparatively  recent  years,  was  accom- 
plished by  the  gravity  method.  This  was  called  "gravity  cream- 
ing." As  fat  exists  in  the  form  of  an  emulsion,  by  allowing  milk 
to  rest,  the  globules  will  gather  near  the  surface  of  the  liquid. 
In  so  rising,  they  carry  with  them  certain  of  the  milk  constituents 
such  as  minute  particles  of  milk  sugar,  caseinogen  and  mineral 
matter.  The  earliest  idea  in  creaming  was  the  use  of  the  shallow 
pan,  and  although  rapid  changes  have  been  made  of  late  years, 
a  large  quantity  of  butter  is  still  being  made  by  this  method.  As 
quickly  as  possible  after  milk  has  been  drawn  from  the  cow,  it 
is  run  into  shallow  pans,  cooled  and  placed  in  a  clean,  well  venti- 
lated cellar  where  it  is  kept  about  thirty-six  hours  at  a  tempera- 
ture approximating  60°  F.  After  the  fat  has  gathered  at  the 
top,  it  is  removed  by  a  skimmer.  With  this  method  the  separa- 
tion is  imperfect,  as  about  20  per  cent,  of  the  fat  remains  with 
the  skim  milk. 

The  use  of  deep  pans  for  creaming  has  been  very  popular  in 
many  parts  of  Europe  for  the  past  thirty  years.  The  tempera- 
ture of  the  milk  is  rapidly  dropped  to  40°  F.  where  it  is  main- 
tained by  ice  or  cold  water  from  twelve  to  twenty-four  hours. 
This  insures  a  more  perfect  separation  of  the  cream,  the  loss 
involved  under  favorable  conditions  being  less  than  one-half  the 
amount  which  occurs  in  the  shallow  pan  method. 

In  the  United  States  the  deep  setting  system  has  never  been 
largely  employed.  This  is  undoubtedly  due  to  the  fact  that 
shortly  after  its  introduction  abroad,  a  machine  was  patented  by 


FOOD   INDUSTRIES 


179 


which  fat  could  be  removed  from  milk  by  centrifugal  force. 
Although  the  cream  separators,  as  they  are  called,  were  at  first 
very  crude,  it  is  to  their  development  that  we  owe  revolutionizing 
methods  in  butter-making  (Fig.  48).  In  separating  cream  by 
this  method,  much  labor  is  saved  and  less  loss  is  involved.  The 
separator  consists  of  a  revolving  bowl  or  drum  usually  made  of 
cast  iron.  Old-fashioned  types  have  hollow  drums,  but  modern 
separators  contain  contrivances  in  the  bowl  to  increase  the  effi- 
ciency of  separation  (Fig.  49).  An  entrance  is  made  for  the 
whole  milk  and  suitable  openings  for  the  removal  of  the  cream 


Fig.  48. — Early  Experiment  in  Cream  Separator. 
(Courtesy  of  the  De  Laval  Cream  Separator  Co.) 

and  the  skim  milk.  When  the  bowl  is  rapidly  revolved,  the 
heavy  liquid  is  thrown  toward  the  outer  wall  from  where  it 
finds  an  exit  through  the  skim  milk  tube.  The  cream  being 
lighter  moves  toward  the  center  and  is  drawn  off  through  the 
cream  outlet.  The  separation  can  be  carried  almost  to  perfect. 
The  cream  separator  also  assists  in  clarifying  milk,  as  much 
dirty  material  is  thrown  against  the  outer  wall  of  the  bowl,  and 
can  be  removed  from  the  skim  milk  by  screening. 

Ripening  of  the  Cream. — It  is  possible  to  make  butter  directly 
from  sweet  cream,  but  such  a  product  lacks  the  delicate  flavor 
and  texture  of  butter  which  has  passed  through  a  ripening  pro- 


i8o 


FOOD   INDUSTRIES 


cess,  and  it  does  not  keep  as  well.  This  process  is  essentially  the 
holding  of  cream  under  favorable  conditions  for  a  period,  in 
order  to  allow  bacterial  action  to  take  place.  Such  action  may 
be  brought  about  by  bacteria  of  the  air  or  those  natural  to  milk, 


SIMPLE  CREAM  SCREW 
ADJUSTMENT 


SIGHT  FEED  LUBRICAT 
(SOLE  OIL  SUPPLY) 


CENTER  BALANCED  BOWL 


SPLIT-WING  TUBULAR 
OR  FEEDING  SHAFT 


ONE  PIECE  DETACHED  SPINDLE 


SEAMLESS  ANTI-SPLASH 
SANITARY  SUPPLY  CAN 


SANITARY  FAUCET 
EXTRA  HEAVY  TINWARE 
REVERSIBLE  FLOAT 


MPROVED    ALPHA-DE  LAVAL- 
SEPARATING  DISCS 


HEAVY  PART  OF  BOWL 
BELOW  CENTER  OF  GRAVITY 


HIGH  BEARING  CASE  PROTECTING 
GEARS  FROM  MILK  AND  WATER 


HELICAL  TOOTH  SPUR.  PINION 
AND  WORM  WHEEL  GEARS 


BRONZE  REVERSIBLE  WORM  WHEEL 
FRAME  JOINING  SCREW- 
OPEN.  SANITARY  BASE 


SIMPLE  ONE  PIECE  SPRING  SPINDLE 
BEARING  WITH  DUST  COVER 


SIMPI  E  LOWER  BEARING  AND  FRICTIONLESS 
STEEL  CARRYING  POINTS 


ADJUSTABLE  PAIL  SHELF 
DRAIN  COCK  FOR  DRIP  SHELF 


Fig.  49.— Improved  De  I. aval  Cream  Separator. 
(Courtesy  of  the  De  Laval  Cream  Separator  Co.) 

causing  the  development  of  lactic  acid.  The  temperature  during 
this  process  is  regulated  from  60° -70°  F.  and  absolute  cleanli- 
ness has  been  found  to  be  essential.  Any  carelessness  at  this 
stage  is  apt  to  cause  other  ferments  to  work  upon  the  milk  and 


FOOD   INDUSTRIES  l8l 

undesirable  flavors  to  be  developed.  In  order  to  have  a  uniform 
taste  to  butter,  the  cream  is  sometimes  pasteurized,  cooled  and 
artificial  bacterial  cultures  are  added.  Their  use  was  first  sug- 
gested by  the  people  of  Denmark,  who  now  employ  this  process 
largely.  Professor  Conn,  of  Wesleyan  University,  also  highly 
recommends  their  use,  but  they  have  never  been  as  popular  in 
America  as  they  have  been  abroad.  The  majority  of  experts  prefer 
the  flavor  of  butter  which  has  been  ripened  naturally  under 
thoroughly  sanitary  conditions. 

The  amount  of  acid  allowed  to  develop  depends  on  the  taste 
desired.  Experienced  butter-makers  usually  judge  by  the  appear- 
ance and  flavor  or  tests  can  be  made  for  acidity  by  the  use  of 
normal  alkali  solutions.  Under-ripening  gives  an  insipid  tasting 
product,  while  over-ripening  causes  the  development  of  unde- 
sirable flavors  and  gives  a  poor  texture. 

Churning. — By  agitation,  it  is  possible  to  separate  out  the  fat 
in  mass,  from  the  ripened  cream,  so  it  can  be  readily  removed 
from  the  milk  serum.  As  before  mentioned  the  primitive 
churns  were  undoubtedly  made  from  the  skins  of  animals,  and 
the  old-fashioned  dash  churn  worked  by  hand  represents  another 
simple  form.  Now  churns  are  run  by  machinery  and  may  be 
rotating  hollow  barrels,  square  boxes  or  more  elaborate  forms 
which  combine  churn  and  butter  worker.  The  best  temperature 
for  the  rapid  gathering  of  the  fat  is  65°-7o°  F..  and  under  fav- 
orable conditions,  butter  will  appear  in  from  12  to  30  minutes. 
It  can  then  be  easily  separated  from  the  butter-milk. 

Washing  and  Working. — In  order  to  prepare  butter  for  the 
market,  it  is  necessary  to  subject  it  to  a  washing,  seasoning  and 
working  process.  The  washing  with  water  removes  the  remain- 
ing butter-milk,  but  should  be  carried  out  with  great  caution,  as 
much  of  the  desirable  flavor  of  butter  is  soluble  in  water.  Brine 
may  be  used  for  wash  water  or  dry  salt  may  next  be  added,  and 
the  mass  worked  into  a  compact  form.  The  working  process 
also  separates  from  the  butter  certain  non-fatty  constituents  of 
the  cream,  which  greatly  assist  in  the  keeping  quality  and  give 
to  the  butter  a  finer  texture.  Salt  is  added  to  give  flavor  rather 


1 82  FOOD    INDUSTRIES 

than  for  its  antiseptic  properties.  The  amount  should  be  small 
or  the  butter  will  be  unpalatable.  Many  prefer  the  taste  without 
the  addition  of  salt.  The  product  is  called  sweet  butter  and  is 
generally  considered  the  highest  grade  butter  on  the  market. 

Coloring. — The  coloring  of  butter  with  annatto,  saffron  or 
coal  tar  dyes  is  very  largely  practiced  in  the  United  States.  The 
natural  coloring  of  milk  varies  with  the  seasons.  When  cows 
are  fed  on  fresh  pasture  grasses  the  butter  is  a  clear  bright 
golden  yellow,  but  during  the  winter  months  when  stall  feeding 
is  necessary,  it  develops  only  a  slight  yellowish  appearance.  Since 
the  demand  is  for  yellow  butter,  it  has  become  customary  to  add 
coloring  matter  during  the  working  process.  Although  as  a  rule, 
it  is  harmless,,  the  use  cannot  be  recommended. 

Flavor. — The  flavor  of  butter  depends  largely  on  the  character 
of  food  given  to  the  cow,  to  careful  methods  of  manufacture, 
to  the  amount  pf  salt  added,  and  to  sanitary  conditions  during 
the  ripening  process  and  during  storage. 

RENOVATED  BUTTER. 

A  product  known  as  renovated,  process  or  hash  butter  has  of 
late  years,  been  placed  upon  the  market.  The  material  from 
which  it  is  made  is  gathered  from  dairies  scattered  over  a  wide 
area.  Dairy  butter  made  under  different  conditions  will  vary 
greatly  in  color,  texture  and  flavor.  When  taken  to  a  central 
creamery,  these  butters  are  mixed  together,  melted,  purified  of 
the  rancidity  by  washing,  coloring  matter  is  added  and  the  re- 
sulting mass  is  rechurned.  While  the  product  may  be  better  than 
a  poor  quality  butter,  there  is  danger  of  more  or  less  rancidity  in 
renovated  butter.  This  is  caused  by  the  purifying  process  being 
insufficient,  as  a  prolonged  washing  would  remove  the  butter-fats 
which  are  so  essential  to  the  flavor  of  butter. 

OLEOMARGARINE. 

The  manufacture  of  substitutes  for  normal,  dairy  butter  began 
in  1870  with  the  experiments  of  Mege-Mouries,  who  suggested 
the  use  of  cheaper  fats,  as  a  basis  for  the  preparation  of  a  prod- 
uct to  be  used  in  the  place  of  butter.  These  substitutes  have 


FOOD   INDUSTRIES  183 

been  placed  on  the  market  under  varying  names  such  as  oleomar- 
garine, oleo,  butterine  and  lardine,  but  all  are  called  oleomar- 
garine by  the  United  States  Government. 

Oleomargarine  has  been  greatly  misrepresented  since  the  early 
days  of  its  manufacture.  It  has  been  said  to  be  made  from  soap 
grease,  the  carcasses  of  animals  which  have  died  of  disease, 
from  material  extracted  from  sewage  and  other  unwholesome 
fatty  matter.  These  statements  have  been  far  from  the  truth, 
for  oleomargarine  is  made*  from  pure  material,  in  the  cleanest 
possible  manner  and  under  the  supervision  of  the  Officials  of 
the  Internal  Revenue.  When  well  made  it  is  equally  as  whole- 
some as  butter,  and  is  a  very  valuable  article  in  the  diet  of  those 
who  cannot  afford  to  buy  a  good  quality  butter.  When  sold 
under  its  own  name,  it  is  a  product  well  worth  being  on  the 
market.  The  chief  objection  has  been  the  enormous  amount  of 
fraud  practiced.  Since  the  early  days  of  its  manufacture,  there 
has  been  a  constant  disposition  on  the  part  of  the  manufacturer 
and  local  dealer  to  sell  it  as  butter  and  in  spite  of  government 
inspection,  this  fraud  is  still  largely  practiced. 

Materials  Used. — The  fats  utilized  as  a  basis  for  butter  substi- 
tutes are  those  which  have  been  in  the  diet  of  civilized  people 
for  centuries.  Mege-Mouries  suggested  the  use  of  carefully 
washed  beef-suet.  Neutral  lard,  lard  stearin,  cottonseed  oil  and 
cottonseed  oil  stearin  are  now  also  largely  used.  Milk  is  added 
to  give  flavor  and  occasionally  egg-yolks  to  give  coloring  and  a 
firmer  structure.  Salt  and  coloring  matter  may  or  may  not  be 
added.  The  government  requires  a  tax  of  ten  cents  per  pound 
for  all  oleomargarine  colored  to  resemble  butter. 

Processes  in  Manufacture. — Fats  are  taken  from  the  slaughter- 
house, washed  and  cooled  as  quickly  as  possible  to  remove  animal 
heat.  They  are  cut  by  machinery  into  small  pieces,  heated  to 
separate  fat  from  the  tissue,  cooled,  stearin  is  removed  by 
presses  and  the  remaining  fat  is  known  as  oleo  oil.  To  oleo  oil 
a  small  quantity  of  neutral  lard  is  added  to  give  body.  These 
fats  are  melted,  filtered  and  churned  with  milk  which  has  been 
ripened,  in  a  like  manner  to  that  employed  by  butter  makers  in 
13 


1 84 


FOOD    INDUSTRIES 


most  creameries.  When  the  churning  process  is  complete,  the 
butterine  is  drawn  off  into  vats  filled  with  ice  water  which  causes 
the  fat  to  solidify  into  small  masses  (Fig.  50).  The  butterine  is 
removed  by  cloth  covered  screens  and  deposited  on  trays,  with 
perforated  bottoms,  where  it  is  allowed  to  remain  until  excess 
water  has  drained  off.  After  the  addition  of  salt,  butter  is 


Fig.  50. —Chilling  Butterine.     (Courtesy  of  Armour  &  Co.,  Chicago,  111.) 

worked  and  finished  for  the  market  in  a  manner  similar  to  the 
processes  used  in  butter-making. 

OLIVE  OIL. 

Olive  oil  was  the  first  of  the  vegetable  oils  used  by  the  human 
race,  and  from  the  standpoint  of  the  palatability  it  still  holds  the 
first  place.  It  has  been  known  from  the  earliest  historic  times 
and  is  supposed  to  have  been  introduced  into  Europe  from  Asia 
Minor. 

Olive  oil  is  obtained  from  the  fruit  of  the  olive  tree  where  it 


FOOD   INDUSTRIES  185 

makes  up  from  40-60  per  cent,  of  the  weight  of  the  fruit.  The 
oil  is  found  in  both  pulp  and  kernel,  but  the  pulp  yields  the  better 
quality.  The  olive  tree  grows  in  semi-arid  regions,  where  rain- 
fall is  not  abundant  and  where  the  temperature  is  fairly  high. 
Spain,  Italy,  Greece,  Southern  France  and  Southern  California 
are  the  principal  regions  where  the  olive  tree  is  grown. 

Olives  are  usually  picked  when  they  are  three-quarters  ripe 
and  for  the  best  grade  oils  are  carefully  sorted.  For  these  oils 
the  choicest  olives  only  are  selected  and  are  bruised  very  slightly 
in  a  mill.  Only  the  pulp  and  not  the  kernel  is  crushed.  The 
crushed  pulp  is  then  gathered  up  and  the  oil  is  allowed  to  drain 
away,  without  heat,  and  either  without  or  with  slight  pres- 
sure. This  product  is  known  as  "Virgin  Oil."  It  has  a  yellowish 
appearance,  a  very  delicate  flavor  and  has  excellent  keeping 
properties.  Heat  and  more  pressure  are  applied  for  a  second  grade 
oil.  For  ordinary  lower  grade  olive  oil  both  pulp  and  stones 
are  ground  into  an  oily  paste,  which  is  packed  into  woven  grass 
bags  and  subjected  to  pressure.  The  process  is  continued  until 
all  the  oil  has  been  extracted.  The  different  grades  are  refined 
by  heating  to  coagulate  albuminous  matter,  which  is  allowed  to 
settle.  The  lighter  colored  oils  are  used  for  the  table,  the  darker 
for  soap-making,  lubricating  purposes  and  the  like. 

Adulteration. — There  has  been  an  enormous  amount  of  adul- 
teration- practiced  with  olive  oil  on  account  of  the  great  demand, 
the  high  price  and  the  ease  of  substituting  other  vegetable  oils. 
Nearly  all  of  the  vegetable  oils  have  the  same  amber  tint  as  olive 
oil,  and  wrhen  added  in  certain  proportions  can  scarcely  be  de- 
tected by  taste.  Abroad  peanut  oil  has  been  largely  substituted 
for  olive  oil  and  in  the  United  States,  cottonseed  oil  has  fur- 
nished the  chief  adulterant. 

COTTONSEED  OIL. 

Until  comparatively  recent  years,  the  cotton  plant  which  is 
cultivated  so  largely  in  the  Southern  States,  was  used  only  for 
its  fiber.  The  seed,  however,  has  been  found  to  be  particularly 
rich  in  oil,  and  rapid  development  in  methods  of  extraction  and 
purification  have  opened  up  a  new  industry,  and  have  placed 


1 86  FOOD   INDUSTRIES 

upon  the  market  a  comparatively  cheap  and  nutritious  edible  oil. 
Processes  in  Manufacture. — The  seeds  when  taken  to  the  mill 
are  screened,  passed  over  magnetic  iron  plates  and  through  ma- 
chines known  as  linters  to  remove  foreign  material  such  as  sand, 
nails  and  cotton  fiber.  The  short  fiber  obtained  in  the  linters 
can  be  used  for  the  preparation  of  cotton  batting.  The  cleaned 
seeds  are  hulled,  crushed  and  heated.  The  cooked  meal  is  en- 
closed in  camel's-hair  cloth  and  subjected  to  hydraulic  pressure, 
by  which  means  the  oil  is  removed.  Crude  cotton  seed  oil  is  red- 
dish in  color  and  must  be  refined.  This  is  accomplished  by  the 
following  processes.  After  the  addition  of  10  Be  NaOH,  the 
oil  is  heated  to  8o°-85°  C.  and  the  mass  is  constantly  stirred 
with  paddles,  until  fatty  acids  are  neutralized  and  impurities  pre- 
cipitate out.  It  is  then  allowed  to  remain  quiet  for  many  hours 
in  a  'settling  tank,  after  which  the  "foots"  are  removed  and  sold 
to  soap  manufacturers.  The  clarified  fat  is  bleached  with  Ful- 
ler's earth  and  the  color  and  taste  are  removed  by  secret  pro- 
cesses. If  it  is  to  be  sold  as  salad  oil,  it  is  winterized  by  drop- 
ping the  temperature  and  removing  by  filtration,  any  fatty  mat- 
ter which  has  solidified.  The  oil  must  stand  eight  hours  at  the 
temperature  of  refrigeration  before  it  is  bottled. 

PEANUT  OIL. 

Peanut  oil  is  extracted  from  the  peanut  by  the  hydraulic  pres- 
sure method,  and  is  refined  by  processes  quite  similar  to  those 
used  with  olive  oil.  The  first  pressing  gives  an  edible  oil,  used 
extensively  in  Europe  and  to  a  limited  extent  in  the  United 
States  for  salad  dressing,  either  alone  or  mixed  with  other  oil. 
Subsequent  pressing  yields  a  product  very  frequently  employed 
in  France  for  packing  cheaper  qualities  of  sardines  and  other 
food  products.  Peanut  oil  is  also  utilized  in  the  making  of  fine 
silks  as  it  does  not  readily  turn  rancid,  and  as  a  lubricant  for 
fine  machinery  because  it  does  not  have  the  tendency  to  "gum." 
Inferior  qualities  are  used  in  soap-making  and  as  a  basis  for 
liniment.  The  cake  which  is  left  after  the  final  pressing  is 
highly  prized  for  cattle  food,  as  it  contains  oil,  protein  and  min- 
eral matter.  It  may  also  be  utilized  as  a  fertilizer. 


CHAPTER  XIV. 


ANIMAL  FOODS- 

The  animal  foods  commonly  utilized  by  man  in  civilized'  coun- 
tries include  the  flesh  and  various  organs  of  cattle,  sheep  and 
swine,  domestic  and  wild  fowl,  fish  and  shellfish,  eggs,  milk  and 
milk  products. 

MEAT. 

In  the  United  States,  the  term  meat  generally  implies  the 
edible  portion  of  cattle,  sheep  or  swine.  Animals  found  in  the 
wild  state,  as  the  deer,  moose,  bear,  squirrel  and  rabbit,  are  fre- 
quently highly  prized  but  are  used  only  to  a  limited  extent. 

The  Physical  Structure  and  Chemical  Constitution. — Whether 
of  domestic  or  wild  origin,  the  muscle  of  meat  is  found  to 
have  a  similar  structure  when  viewed  through  a  microscope.  It 
appears  to  consist  of  tiny  fibers  which  have  the  form  of  tubes, 
varying  in  length  in  different  kinds  of  meat  and  in  different 
parts  of  the  same  animal.  The  walls  of  the  tubes  consist  of  a 
protein  substance  which  in  the  living  animal  is  very  elastic.  It 
is  known  as  elastin  or  yellow  connective  tissue.  The  tubes  are 
bound  together  in  bundles  by  a  thin  membrane  called  collagen 
or  white  connective  tissue,  a  substance  of  great  importance  since 
it  yields  gelatin  on  boiling.  Commercially  gelatin  may  also  be 
obtained  from  the  elastin  by  the  addition  of  an  acid,  but  in  the 
household  elastin  is  not  materially  affected  by  cooking,  except 
that  it  shows  a  tendency  to  harden. 

The  texture  of  meat  depends  upon  the  amount  of  connective 
tissue  present,  the  contents  of  the  tubes  and  upon  the  character 
of  the  walls  of  the  muscle  tubes.  In  a  young,  well-fed  animal, 
the  wall  of  these  tubes  is  a  thin  delicate  membrane  and  there  is 
little  connective  tissue.  The  meat  is,  therefore,  tender.  The  older 
an  animal  is,  however,  and  the  more  work  it  has  been  required 
to  do,  the  denser  becomes  the  membrane  and  the  larger  the 
amount  of  connective  tissue,  thus  giving  a  tough  texture  to  the 
meat. 

The  value  of  the  meat  as  food  depends  largely  on  the  fat  and 


1 88  FOOD   INDUSTRIES 

the  contents  of  the  muscle  tubes,  which  are  chiefly  protein.  In 
the  living  animal  within  the  muscle  tubes  may  be  found  liquid 
myosinogen,  paramyosinogen,  albumin,  alkaline  salts  and  ex- 
tractives. Carbohydrate  occurs  in  the  form  of  glycogen  and 
glucose.  As  glycogen  is  not  stored  in  large  amounts  it  disap- 
pears very  shortly  after  death.  The  texture  of  meat  also  changes 
considerably  at  death,  caused  by  the  clotting  of  the  principal 
proteins,  myosinogen  and  paramyosinogen.  The  hardening  of 
the  muscle  tubes  known  as  rigor  mortes  or  the  death-stiffening 
causes  the  meat  to  become  very  tough  and  it  should,  therefore, 
never  be  eaten  in  this  stage.  Either  meat  should  be  consumed 
before  stiffening  has  had  time  to  set  in,  or  it  should  be  hung  until 
further  changes  take  place,  which  again  give  it  a  tender  texture. 
Rigor  mortes  is  succeeded  by  the  first  stages  of  decomposition, 
during  which  acids  are  developed  which  not  only  bring  about 
important  chemical  changes,  but  develop  desirable  flavors,  fresh 
meat  being  very  insipid.  The  contents  of  the  muscle  tubes, 
therefore,  differ  after  hanging.  They  are  found  to  contain  myo- 
sin,  metaprotein,  extractives,  mineral  matter  and  sarco-lactic 
acid. 

Fat. — All  meat,  however  lean  it  may  appear,  contains  fat. 
Besides  that  ordinarily  visible  there  is  always  present  more  or 
less,  occurring  in  small  particles,  embedded  in  the  connective  tis- 
sue between  the  muscle  fiber.  The  visible  fat  varies  greatly  in 
amount,  being  comparatively  small  in  veal,  chicken  and  most 
game,  while  in  pork,  fattened  beef  and  mutton  and  in  the  duck 
and  the  goose,  the  amount  may  reach  one  quarter  to  one  half  of 
the  weight  of  the  entire  animal. 

Water. — The  amount  of  water  contained  in  meat  also  differs 
widely,  being  regulated  to  a  great  extent  by  the  fat  content  as 
other  constituents  are  fairly  constant. 

.  Mineral  Matter. — While  protein  is  the  chief  constituent  of 
meat,  the  mineral  matter  which  it  contains,  particularly  the  phos- 
phorus compounds,  is  also  important  although  it  occurs  in  rela- 
tively small  quantities,  constituting  about  0.3  to  1.9  per  cent,  of 
the  total  fresh  material.  Besides  phosphorus,  meat  contains  po- 


FOOD   INDUSTRIES  189 

tassium,    sulphur,    sodium,    magnesium,    calcium    and   chlorides. 
Traces  of  iron  are  found  in  lean  beef,  bacon  and  ham. 

.  Meat  Inspection. — Since  domestic  animals  are  subject  to 
diseases  which  can  be  transmitted  to  man,  a  more  or  less  rigid 
government  inspection  is  now  carried  on  by  most  civilized  coun- 
tries. Chief  among  these  diseases  are  tuberculosis  found  prin- 
cipally in  cattle  and  swine,  and  trachina  which  occurs  exclu- 
sively in  swine. 

Tuberculosis— Tuberculosis  is  probably  the  most  frequently 
occurring  disease  both  in  this  country  and  abroad.  Among  cat- 
tle it  has  probably  been  the  most  widespread,  occurring  not  only 
in  animals  intended  for  slaughter  but  among  dairy  cows,  par- 
ticularly those  of  the  Jersey  and  Guernsey  herds.  Much  ex- 
perimentation has  been  carried  on  for  many  years,  to  determine 
at  what  stage  meat  from  animals  affected  with  tuberculosis  be- 
comes unfit  for  human  consumption.  ,  Experts  still  disagree  on 
this  subject.  Extremists  advise  the  condensing  of  the  entire 
carcass  even  though  the  disease  may  be  in  an  early  stage  and 
localized.  Most  authorities,  however,  take  a  more  moderate 
view  and  would  allow  meat  to  be  sold  for  food  where  the  disease 
does  not  exist  in  a  dangerous  form,  or  where  it  is  more  or  less 
restricted  to  certain  organs.  Where  the  disease  has  become  gen- 
eralized, all  agree  that  the  entire  carcass  should  be  condemned. 
With  modern  packing  house  methods,  it  has  been  found  that 
even  such  animals  may  be  utilized  for  the  manufacture  of  valu- 
able fertilizing  material. 

Trachina. — Swine  are  sometimes  found  to  be  infected  with 
trachina,  a  disease  resulting  from  a  minute  parasitic  worm,  which 
usually  invades  the  muscular  tissues.  It  was  long  regarded  as 
a  harmless  parasite,  but  is  now  known  to  cause  a  disease  in  the 
human  family  somewhat  similar  to  typhoid  fever.  Fortunately 
it  is  killed  when  exposed  to  a  temperature  of  i55°-i6o°  F.  As 
it  is  customary  in  the  United  States  to  consume  pork  well  cooked, 
there  is  practically  little  danger  from  this  disease.  Abroad 
where  it  is  eaten  more  or  less  rare,  a  rigid  inspection  has  been 
found  necessary. 


190  FOOD    INDUSTRIES 

Reasons  for  Cooking  Meat. — In  great  contrast  to  the  carbo- 
hydrate group,  protein  does  not  become  more  digestible  on  cook- 
ing. In  fact,  meat  fiber  subjected  to  high  temperature  or  pro- 
longed heating  becomes  toughened  and  more  difficult  of  diges- 
tion. It  is  obvious,  therefore,  that  we  must  look  for  other  rea- 
sons for  the  almost  universal  custom  of  cooking  meat.  Sterili- 
zation is  the  reason  usually  given,  but  this  is  only  true  to  a  lim- 
ited extent.  As  meat  is  not  a  good  conductor  of  heat,  the  in- 
terior of  large  portions,  such  as  roasts,  frequently  does  not  reach 
the  temperature  when  all  pathogenic  bacteria  are  killed.  Neither 
can  we  hope  that  harmful  ptomaines  will  be  affected  if  by  any 
chance  such  compounds  have  been  developed.  Our  real  reason 
for  cooking  is  probably  the  development  of  desirable  flavors, 
largely  due  to  the  extractive  creatin,  which  yields  creatinin  on 
heating.  This  is  important  as  it  is  now  a  well  known  fact,  that 
we  do  not  derive  as  much  benefit  from  food  that  we  do  not 
relish. 

Changes  in  Cooking. — ist.  The  structure  of  meat  is  frequently 
changed.  Where  wet  heat  or  boiling  is  used,  the  fibers  have  a 
tendency  to  disintegrate.  This  is  caused  by  the  connective  tis- 
sue being  partially  converted  into  gelatin.  2nd.  Certain  losses 
always  occur  in  greater  or  less  amount  according  to  the  method 
of  cooking,  temperature  and  use  of  r^alt.  A  loss  of  water  is 
always  involved  even  when  the  meat  is  boiled.  Part  of  the  fat 
is  removed,  the  amount  depending  on  the  temperature  and  the 
melting  point  of  the  fat.  Soluble  constituents  such  as  albumin, 
mineral  salts,  extractive  and  other  organic  bodies  dissolve,  es- 
pecially in  boiling.  To  prevent  these  soluble  compounds  from 
being  lost,  some  means  are  taken  to  coagulate  the  protein  on  the 
outside,  thus  forming  a  protective  coating.  This  can  be  accom- 
plished by  searing.  The  use  of  salt  and  the  question  of  solu- 
bility are  also  important.  In  soup  and  broth  where  it  is  desir- 
able to  remove  as  much  of  the  nutriment  as  possible,  salt  should 
always  be  added,  as  myosin  as  well  as  albumin  is  soluble  in  a 
dilute  s;aline  solution.  Where  salt  is  used  to  saturation,  as  in 
pickling  or  when  rubbed  on  the  outside  of  a  roast,  myosin  is  re- 


FOOD   INDUSTRIES  IQI 

tained  in  the  meat.    Care  should  be  given  in  pickling  that  satura- 
tion be  kept  up. 

The  greatest  losses  in  cooking  have  been  found  to  be  in  boil- 
ing and  roasting,  protein,  mineral  matter  and  extractives  being  the 
main  constituents  lost  in  boiling,  and  fat  during  the  process  of 
roasting.  According  to  Jordan*  the  smallest  losses  occur  in  pan 
broiling  and  in  sauteing. 

BEEF  EXTRACTS. 

The  question  of  solubility  plays  a  very  important  part  in  the 
preparation  of  beef  extracts,  which  may  be  regarded  as  soup  or 
soup  stock  prepared  from  beef.  The  commercial  forms  are 
more  or  less  concentrated  by  the  water  having  been  removed  in 
vacuo. 

The  valuable  qualities  of  such  extracts  wejre  recognized  by 
old  time  chemists,  but  they  were  not  known  to  any  great  extent 
until  after  the  researches  of  Liebig.  In  1865  a  company  was  formed 
authorized  by  Liebig,  and  a  factory  was  established  in  South 
America,  where  cattle  could  be  extensively  raised  at  a  lower 
cost  than  in  Europe.  The  original  method  of  preparation  of 
these  extracts  was  very  simple.  Finely  chopped  beef  was  treated 
with  eight  times  its  weight  of  cold  water,  and  the  soluble  con- 
stituents were  extracted  by  heating  under  pressure.  The  extract 
was  then  filtered,  the  fat  removed  to  prevent  it  from  becoming 
rancid,  and  the  remaining  liquid  was  concentrated  to  a  paste  in 
a  vacuum  pan.  Liebig  calculated  that  it  would  require  thirty- 
four  pounds  of  meat  to  yield  one  pound  of  beef  extract,  which  on 
dilution  would  make  approximately  six  or  seven  gallons  of  beef 
tea. 

When  extracts  are  made  according  to  this  method,  they  con- 
tain besides  moisture  chiefly  mineral  compounds  17-25  per  cent., 
as  potassium  phosphate  and  sodium  chloride,  and  meat  bases 
50-60  per  cent.,  as  creatin  and  creatinin.  On  examination,  traces 
of  albumin,  proteoses  and  peptone  have  been  found  but  they  arc 
not  present  in  large  enough  quantities  to  add  materially  to  the 
nutritive  value.  During  the  process  of  manufacture,  the  major 

k*  Jordan,  Principles  of  Human  Nutrition,  p.  317. 


192  FOOD   INDUSTRIES 

portion  of  the  beef  containing  practically  all  the  nutriment  is 
rejected.  The  value  of  meat  extracts  must,  therefore,  depend  on 
the  mineral  matter  and  the  meat  bases,  or  as  they  are  frequently 
termed,  the  extractives. 

These  extractives,  of  which  creatin  and  creatinin  are  the  most 
important,  are  nitrogenous  compounds  but  are  not  able  to  fur- 
nish the  body  with  constructive  material,  neither  do  they  yield 
energy.  Beef  extracts  for  that  reason  can  scarcely  be  classed 
as  food.  Experiments  have  revealed  that  animals  fed  exclusively 
on  such  material  died  in  practically  the  same  time  as  those  that 
received  no  food.  Notwithstanding  the  small  amount  of  nutri- 
ment present,  beef  extracts  are  valuable  on  account  of  their 
flavor  and  effect  on  the  digestive  organs.  They  are  the  most 
powerful  exciters  of  the  gastric  secretion  that  we  possess,  and 
are  important,  therefore,  as  arousing  appetite  and  as  an  aid  to 
digestion.  This  is  their  chief  function  in  sickness  and  in  health. 
They  are  also  of  value  as  flavoring  agents. 

Some  commercial  beef  extracts  have  the  addition  of  protein, 
but  the  amount  is  never  very  great,  although  advertising  matter 
frequently  gives  customers  a  false  impression  as  to  their  nu- 
tritive value.  A  series  of  experiments  carried  on  in  1908,  at  the 
Connecticut  Agricultural  Experiment  Station,  showed  that  "Of 
forty-seven  preparations  examined,  ten  only  were  properly 
branded  and  up  to  the  standard,  seventeen  were  found  to  be 
misbranded  and  varying  from  the  standards,  and  the  others  were, 
in  general,  not  up  to  the  standards,  though  not  misbranded." 
The  very  high  cost  of  these  extracts  was  also  reckoned.  It  was 
found  that  the  dry  organic  matter  present  cost  from  $2.68  to 
$10.18  per  pound.  The  amount  far  exceeds  the  cost  of  home 
made  beef  extracts  which  are  as  a  rule  far  better  in  quality. 

Beef  Juices. — Beef  juices  may  also  be  found  on  the  market. 
They  contain  substances  of  the  muscle-fiber  which  may  be  ob- 
tained by  subjecting  finely  chopped  meat  to  strong  pressure,  with 
or  without  the  aid  of  heat,  and  concentrating  the  extracted  liquid 
in  a  vacuum  pan.  Such  products  are  liable  to  undergo  fermenta- 
tion. They  may  readily  be  prepared  in  the  home,  by  placing 


FOOD   INDUSTRIES  193 

finely  chopped  meat  in  a  jar  and  surrounding  it  with  water 
heated  to  140°  F.  The  juice  may  then  be  extracted  from  the 
meat,  by  pressure  with  an  ordinary  lemon  squeezer,  and  flavored 
with  a  small  quantity  of  salt. 

INTERNAL  ORGANS. 

In  the  use  of  internal  organs,  the  custom  differs  in  various 
countries.  On  the  English  market,  quite  frequently  are  seen 
the  heart,  the  lining  of  the  stomach  (tripe),  and  the  kidneys 
particularly  those  of  the  sheep.  While  tripe  and  kidney  may. be 
obtained  in  the  United  States  market,  their  use  is  limited  and 
the  heart  is  considered  of  small  value.  It  is  disposed  of  in  the 
canning  industry  or  more  generally  for  sausage  making. 

Beef  tongues  are  sold  largely  here  and  abroad,  either  smoked 
or  in  the  fresh  state.  As  they  constitute  a  valuable  by-product, 
they  are  handled  with  great  care  in  order  to  prevent  decomposi- 
tion from  setting  in  and  to  give  the  best  results  in  weight  and 
appearance.  Short  tongues  are  frequently  canned,  while  lambs' 
tongues  as  a  rule  are  pickled. 

Beef's  and  sheep's  livers  are  sold  in  the  fresh  state  and  as  they 
become  stale  more  quickly  than  any  other  edible  part  of  the  ani- 
mal, every  effort  is  made  to  keep  them  dry  and  at  a  low  tem- 
perature. They  are  frequently  utilized  in  the  manufacture  of 
sausages  known  as  Liberwurst.  In  the  United  States,  hogs' 
livers  are  seldom  used  for  edible  purposes.  They  frequently  are 
utilized  as  one  of  the  constituents  of  dog  biscuit  or  as  an  in- 
gredient of  table  sauce.  In  former  years,  many  were  shipped  to 
foreign  countries  where  the  custom  of  eating  hogs'  livers  prevails, 
but  more  stringent  laws  in  regard  to  methods  of  preserving  such 
material  during  transportation,  has  greatly  restricted  the  foreign 
trade. 

Calves'  brains  and  sweetbreads  are  considered  delicacies  both  at 
home  and  abroad.  In  the  United  States,  the  thymus  gland  of 
young  animals  is  placed  on  the  market  as  sweetbreads. 

FISH. 

From  the  magnitude  of  the  fish  industry,  both  at  home  and 
abroad,  may  be  seen  the  important  part  that  fish  and  shell-fish 


194  FOOD    INDUSTRIES 

play  in  the  diet  of  the  human  race.  The  catch  in  the  United 
States  alone  reaches  approximately  2,200,000,000  pounds  annu- 
ally, most  of  which  is  consumed  in  this  country,  a  small  propor- 
tion only  being  prepared  in  various  ways  for  export.  Salting, 
smoking,  drying,  canning  and  other  methods  of  preservation, 
have  greatly  increased  the  value  of  fish  as  a  world's  product. 
Modern  methods  of  cold  storage  have  also  greatly  assisted  in  the 
preservation  and  transportation  of  fish.  A  lower  temperature 
than  that  used  with  meat  has  been  found  necessary,  fi:Ji  very  fre- 
quently being  stored  in  the  frozen  state.  While  32°  F.  is  suf- 
ficient to  inhibit  the  growth  of  micro-organisms,  it  will  not  hin- 
der the  action  of  ferments,  which  acting  upon  the  tissues,  produce 
disagreeable  flavors  and  make  the  fish  unpalatable.  Fish  which 
has  been  frozen,  however,  deteriorates  rapidly  when  thawed  and 
decomposition  of  a  very  undesirable  nature  sets  in  quickly.  For 
this  reason,  fish  should  be  eaten  as  fresh  as  possible ;  it  never 
improves  on  keeping  as  does  meat  during  the  hanging  process. 

Fish  living  in  both  salt  and  in  fresh  water  are  generally 
edible,  being,  as  far  as  known  at  the  present  time,  equally  whole- 
some. As  a  rule  those  taken  from  deep,  clear  and  cold  water 
especially  where  the  bottom  is  rocky  or  sandy  are  preferable  to 
those  coming  from  shallow,  warm  water  or  where  the  bottom  is 
muddy.  Fish  taken  from  water  polluted  with  sewage  are  not 
desirable.  It  is  a  well  known  fact  that  some  land-locked  fish 
are  affected  with  parasites,  at  certain  seasons,  which  make  them 
undesirable  as  food. 

Nutritive  Value. — The  nutritive  value  of  fish  is  chiefly  due  to 
the  protein  and  fat  content.  In  protein,  fish  ranks  nearly  as 
high  as  meat,  but  it  is  very  much  poorer  in  fat,  the  majority  of 
species  containing  less  than  5  per  cent.  High  in  fat  are  the 
herring,  lake  trout,  mackerel  and  the  salmon,  ranging  from  7.1 
to  17.8  per  cent.  Many  of  our  common  varieties,  however,  such 
as  the  bass,  bluefish,  cod,  haddock,  perch  and  the  pickerel  con- 
tain less  than  2  per  cent.  The  small  fat  content  of  the  greater 
variety  of  fish  is  the  main  difference  between  meat  and  fish,  when 
compared  as  to  their  relative  nutritive  value.  So  far  as  the 


FOOD   INDUSTRIES 

protein  is  concerned,  fish  resembles  meat  but  great  differences 
occur  in  the  proportion  of  fat  and  water,  fish  having  water 
where  meat  has  fat.  Fish  contains  more  gelatin  yielding  pro- 
teins, but  has  less  extractives.  This  accounts  for  the  lack  of 
flavor  and  the  reason  that  fish  is  apt  to  pall  more  quickly  on  the 
appetite.  The  mineral  matter  consists  chiefly  of  calcium  and 
potassium  phosphate  and  sodium  chloride. 

Edible  Portion. — Large  proportions  of  fish  are  inedible  and 
must,  therefore,  be  considered  as  waste  matter.  This  includes 
the  skin,  scales,  bones,  head,  tail,  entrails  and  fins.  The  amount 
varies  greatly  in  different  varieties,  sometimes  reaching  as  high 
as  70  per  cent.  Taking  fish  of  all  kinds,  according  to  Dr.  Wiley, 
some  55  to  60  per  cent,  of  the  total  weight  is  edible. 

Adulteration. — In  the  fish  market  very  little  adulteration  occurs 
except  along  the  line  of  substitution.  Hake  and  haddock  are 
sometimes  sold  as  cod,  and  inferior  salmon  for  high  priced  vari- 
eties. This  practice  of  substituting  one  variety  of  fish  for  an- 
other occurs  especially  along  the  line  of  canned  goods,  as  in  the 
sardine  canning  industry,  where  the  herring  is  frequently  used. 

SHELLFISH. 

Chief  among  the  shellfish  on  our  market  is  the  oyster  although 
the  clam,  scallop,  lobster,  crab,  shrimp,  turtle  and  terrapin  are 
used  at  certain  seasons,  when  on  account  of  their  cost,  they  are 
usually  considered  great  delicacies.  As  regards  general  com- 
position, they  strongly  resemble  meat  and  fish  except  that  certain 
of  the  shellfish,  as  the  scallop  and  the  oyster,  contain  carbo- 
hydrate in  the  form  of  glycogen. 

The  oyster  has  apparently  occupied  a  place  in  the  diet  of  the 
human  race  for  over  2,000  years.  In  very  remote  ages  the 
Chinese  cultivated  artificial  oyster  beds,  and  as  early  as  100  B.  C. 
the  Italians  were  engaged  in  this  industry.  As  civilization  ad- 
tanced  oyster  farming  spread  to  all  the  maritime  countries  of 
the  Old  World  and  eventually  to  the  Western  Hemisphere, 
where  it  has  progressed  to  such  an  extent,  that  the  annual  crop 
now  exceeds  the. total  production  of  the  rest  of  the  world. 

In  the  United  States  the  oyster  is  extensively  raised  on  the 


196  FOOD    INDUSTRIES 

Atlantic  and  Pacific  Coasts  and  in  the  Gulf  of  Mexico,  especially 
in  the  vicinity  of  Louisiana  and  Texas.  Those  of  the  greatest 
value  come  from  Long  Island  Sound,  while  the  largest  crop  in 
the  world  is  taken  from  the  Chesapeake  Bay. 

Oystermen  formerly  depended  almost  entirely  on  natural  beds 
for  their  product,  but  wherever  the  fishing  is  active  and  the  de- 
mand great,  the  natural  beds  are  rapidly  becoming  exhausted. 
This  has  led  to  the  cultivation  of  artificial  beds  in  close  proximity 
to  public  oyster  grounds.  To  promote  the  oyster  industry  the 
Federal  Government  through  the  Bureau  of  Fisheries,  has  co- 
operated with  the  States  "In  determining  the  physical  and  biologi- 
cal character  of  the  oyster  grounds,  in  surveying  and  plotting 
those  grounds  with  a  view  to  their  allotment  for  oyster  culture, 
in  conducting  experimental  and  model  operations,  in  recommend- 
ing oyster  legislation  and  in  giving  disinterested  expert  advice  on 
the  various  problems  that  arise  in  the  development  and  admin- 
istration of  the  osyter  fishing."* 

The  necessity  of  guarding  oyster  beds  from  sewage  pollution 
has  been  found  imperative,  through  the  tracing  of  typhoid  epi- 
demics to  the  consumption  of  raw  oysters.  For  a  long  period  a 
custom  has  prevailed  among  oystermen  of  transferring  oysters 
from  salt  to  brackisdi  waters,  for  some  forty-eight  hours  before 
shipping.  The  rapid  absorption  of  fresh  water  gives  them  the 
appearance  of  fatness,  increases  their  weight  from  15  to  20  per- 
cent, and  enhances  their  market  value.  The  practice  has  proved 
to  be  unfortunate.  Oyster  plumping  has  been  frequently  carried 
on  in  estuaries  within  range  of  sewers  or  other  sources  of  con- 
tamination. Where  pathogenic  bacteria  exist  in  the  water, 
oysters  are  in  danger  of  imbibing  disease  germs  with  their  food, 
and  of  acting  as  carriers  of  typhoid  to  the  human  family. 
Freshening  also  impairs  the  keeping  quality  and  alters  the  flavor 
through  loss  .of  mineral  matter  by  the  process  of  osmosis. 
Chemical  tests  have  further  showed  that  while  increasing  the 
weight,  fattening  has  deprived  the  oyster  of  10  to  15  per  cent, 
of  its  nutritive  value. 

*  National  Geographic  Magazine,  March  1913. 


FOOD   INDUSTRIES  197 

Deterioration  is  more  rapid  after  removal  from  the  shell ; 
therefore,  while  increasing  the  cost,  it  is  advantageous  to  ship 
oysters  in  the  shell.  They  are,  nevertheless,  frequently  shipped 
without  the  shell  after  having  been  washed  and  placed  .on  ice. 
In  this  form  they  can  be  kept  for  approximately  ten  days. 

As  regards  food  value,  they  are  frequently  compared  to  milk, 
as  both  contain  about  the  same  amount  of  nutritive  substances. 
Comparing  the  relative  cost,  it  may  readily  be  seen  that  the 
oyster  cannot  be  considered  as  an  economical  food.  The  same 
may  be  said  of  the  other  shellfish,  for  while  all  may  be  classed 
as  valuable  foods  so  far  as  protein  and  mineral  matter  are  con- 
cerned, their  high  cost  places  them  among  the  delicacies  rather 
than  among  our  staple  products. 

EGGS. 

Chief  among  the  animal  foods  used  throughout  the  world  are 
eggs.  In  most  countries  hens'  eggs  are  used  to  the  largest  ex- 
tent although  those  of  other  domesticated  animals  such  as  ducks, 
geese,  turkeys  and  guinea-hens  are  frequently  found  on  the 
market.  The  eggs  of  birds  and  reptiles  are  eaten  in  certain 
sections  of  the  world,  and  those  of  the  fish  may  occasionally  be 
found  as  delicacies,  particularly  those  of  the  shad  and  sturgeon, 
the  latter  being  extensively  pickled  and  sold  as  caviar. 

Physical  Structure. — While  the  eggs  of  the  wild  birds  vary 
greatly  in  color,  tint,'  and  plain  or  mottled  appearance,  those  of  the 
hen  are  either  brown  or  white.  Through  a  mistaken  idea  the 
difference  in  hens'  eggs  has  greatly  affected  the  market  value, 
white  eggs  selling  for  a  higher  price  in  some  localities,  while  otjier 
markets  give  the  preference  to  the  brown  varieties.  Analysis  has 
been  carried  on  at  the  New  York  State,  Michigan  and  California 
Experiment  Stations  to  determine  their  relative  nutritive  value. 
After  much  experimentation,  the  conclusion  drawn  was  that 
there  is  no  basis  of  fact  for  such  popular  belief.  "Eggs  of  one 
breed  whatever  the  color  of  the  shells,  are  as  nutritious  as  those 
of  another,  .provided  they  are  of  the  same  size  and  the  fowls  are 
equally  well  fed." 


Ip8  FOOD    INDUSTRIES 

Composition  of  the  Shell. — The  shell  or  protective  coating  of  the 
egg  is  very  largely  composed  of  mineral  matter.  According  to 
Dr.  Langworthy  93.7  per  cent,  is  calcium  carbonate  while  mag- 
nesium carbonate  and  calcium  phosphate  also  appear  in  small 
amounts.  Organic  matter  is  present  only  to  the  extent  of  4.2 
per  cent. 

When  viewed  through  a  magnifying  glass,  the  shell  is  shown 
to  be  very  porous  in  its  nature.  This  allows  the  evaporation  of 
water  and  results  in  the  gradual  loss  in  weight  of  the  egg.  The 
decrease  in  specific  gravity,  therefore,  furnishes  a  very  satisfac- 
tory means  of  judging  the  freshness  of  an  egg.  Brine  may  be 
prepared  by  dissolving  2  ounces  of  salt  in  i  pint  of  water.  A 
perfectly  fresh  egg  will  sink  to  the  bottom  in  this  solution.  Ac- 
cording to  the  experiments  of  Siebel,  "An  egg  one  day  old  will 
sink  below  the  surface,  but  not  to  the  bottom,  while  over  three 
days  old  will  float  on  the  surface,  the  amount  of  shell  exposed 
increasing  with  age." 

In  marketing  eggs,  the  freshness  is  usually  told  by  a  process 
called  "candling."  In  a  dark  room,  an  egg  is  held  between  the 
eye  and  an  artificial  light ;  a  fresh  egg  appears  unclouded,  homo- 
geneous and  translucent;  a  stale  egg  is  cloudy  and  frequently 
contains  dark  spots;  a  rotten  egg  appears  dark  colored.  A  sim- 
ple housewife's  test  may  also  be  made  by  shaking  an  egg  held 
near  the  ear.  The  contents,  of  the  egg  should  not  move.  If  a 
slight  movement  can  be  detected,  it  is  somewhat  stale ;  if  it 
rattles,  the  egg  is  spoiled. 

Methods  of  Preservation. — The  porous  condition  of  the  shell 
is  to  a  great  extent  responsible  for  the  rapid  deterioration  of  eggs. 
Bacteria  can  readily  enter  and  bring  about  such  changes  as  to 
make  the  article  unfit  for  human  consumption,  in  a  comparatively 
short  time. 

In  early  days  eggs  were  usually  marketed  near  the  source  of 
supply,  but  modern  times  frequently  require  the  transportation 
for  long  distances.  As  hens  lay  more  plentifully  in  the  spring 
it  is  also  necessary,  in  order  to  secure  an  even  distribution 
throughout  the  year,  to  store  eggs  for  use  during  the  fall  and 


FOOD   INDUSTRIES  199 

winter  months.  These  facts  have  led  to  the  study  of  the  best 
methods  of  preservation.  Cold  storage  has  been  found  most 
effective,  a  temperature  near  the  freezing  point  being  usually 
employed.  Eggs  thus  protected  retain  their  freshness  for  several 
weeks,  but  when  held  for  months  as  is  frequently  the  case,  the 
taste  and  odor  are  greatly  altered.  Where  decomposition  has  not 
set  in  such  eggs  can  be  readily  used  for  cooking  purposes. 

In  order  to  prevent  bacteria  from  entering,  eggs  are  sometimes 
coated  with  a  non-porous  substance.  The  most  efficient  of  these 
has  been  found  to  be  a  10  per  cent,  solution  of  sodium  silicate 
(water-glass).  The  egg  should  be  carefully  wiped  with  a  damp 
cloth,  and  either  coated  or  placed  in  a  jar  containing  the  water- 
glass  as  quickly  after  it  has  been  laid  as  possible. 

Eggs  may  also  be  preserved  by  the  process  of  drying.  Desi- 
cation  may  be  accomplished  by  spreading  the  egg  in  a  thin  film 
on  a  dry  surface,  or  by  passing  the  product  under  pressure 
through  drying  chambers.  Where  fresh  eggs  have  been  used, 
and  where  the  process  of  manufacture  is  such  as  to  make  the 
product  palatable  and  care  has  been  given  to  the  storage,  such 
a  product  is  wholesome  and  may  be  held  for  a  reasonable  length 
of  time.  Dried  eggs  are  used  largely  by  bakers,  in  carnps  and 
on  long  expeditions  where  fresh  eggs  are  not  available. 

Composition  of  an  Egg. — As  the  contents  of  an  egg  were  in- 
tended by  nature,,  to  furnish  the  sole  nutrition  of  the  young  chick 
during  the  process  of  development,  we  might  expect  to  find  among 
its  constituents,  all  the  elements  required  for  building  purposes. 
In  this  way  it  bears  a  strong  resemblance  to  milk,  both  being  a 
perfect  food  for  the  animal  for  which  it  is  intended.  Water, 
protein,  fat  and  mineral  matter  are  well  represented,  while  carbo- 
hydrate is  present  only  in  a  small  amount.  The  nutritive  parts 
of  the  white  are  chiefly  protein,  largely  in  the  form  of  albumins, 
and  a  small  amount  of  mineral  matter.  Only  traces  of  fat  are 
present.  The  yolk  is  rich  in  fat,  protein  and  mineral  matter. 
The  fat  occurs  in  the  form  of  an  emulsion,  held  in  suspension  by 
Vitellin,  a  phosphoprotein  resembling  the  caseinogen  of  milk. 
Eggs  are  also  rich  in  sulphur,  phosphorus  and  such  elements  as 


200 


FOOD   INDUSTRIES 


calcium,  magnesium,  potassium  and  iron  in  the  form  of  salts. 
Another  important  food  constituent  present  in  the  yolk  is  lecithin^ 
a  compound  which  furnishes  the  body  with  phosphorus  in  a 
form  which  can  be  readily  assimilated.  The  composition  of  the 
white  and  yolk,  given  by  Langworthy  is  as  follows : 


White 

Yolk 

Water  

86.2 
12.3 
O.2 

49-5 
IS-? 
33-3 

Fat  

CHAPTER  XV. 


THE  PACKING  HOUSE. 

Historical. — The  packing  industry  as  it  exists  to-day  was 
founded  about  thirty  years  ago,  although  packing  in  a  very  prim- 
itive way,  has  been  practiced  since  the  middle  of  the  i8th  cen- 
tury. Starting  in  the  eastern  United  States,  it  spread  westward 
and  in  time  concentrated  in  centers  near  the  source  of  supply 
of  the  raw  material,  thus  saving  the  cost  of  freight  on  the  live 
animal,  from  the  ranch  to  the  market. 

On  account  of  the  large  grazing  areas,  it  became  possible  to 
raise  cattle  in  the  west  in  larger  numbers  than  in  the  more  settled 
east,  so  we  find  Chicago,  Kansas  City,  St.  Louis,  Omaha,  St. 
Joseph,  Fort  Worth  and  other  middle  west  cities  rapidly  becoming 
important  packing  house  centers.  The  nearness  to  the  corn  belt 
and  the  water  or  rail  shipping  facilities  have  also  played  an  im- 
portant part  in  the  development  of  these  cities,  as  centers  in  the 
packing  industry. 

The  growth  of  this  business  has  been  very  rapid.  Although 
of  comparatively  recent  origin,  it  now  ranks  fifth  in  importance 
of  the  industries  of  the  United  States.  It  is  said  to  be  the 
largest  and  most  important  industry  which  is  strictly  American  in 
its  conception  and  development.  From  the  States,  it  is  rapidly 
spreading  to  most  of  the  new  countries  of  the  world. 

Growth  and  Breadth,  of  the  Industry. — Important  factors  lead- 
ing to  the  rapid  growth  of  the  packing  business  have  been  arti- 
ficial refrigeration,  concentration  and  the  utilization  of  by-pro- 
ducts. 

In  former  times,  packing  could  only  be  carried  on  during  the 
winter  months,  as  meat  cannot  be  kept  in  good  condition  for  any 
length  of  time  after  slaughtering,  unless  the  temperature  is  kept 
low.  The  introduction  of  artificial  refrigeration  has  now  made 
it  possible  to  carry  on  the  business  throughout  the  year.  Not 
only  has  refrigeration  become  essential  in  the  packing  house,  but 
its  use  during  transportation  has  regulated  the  supply  of  meat  at 
all  seasons. 


2O2  FOOD    INDUSTRIES 

Where  animals  were  driven  or  shipped  to  the  place  of  consump- 
tion and  slaughtered  for  local  demand,  the  numbers  were  neces- 
sarily very  small  and  little  thought  was  given  to  the  by-products. 
The  fresh  beef,  the  hide,  the  horns  and  the  tallow  were  the  only 
products  used ;  the  remainder  was  thrown  away.  This  involved 
a  great  waste  of  valuable  material.  When  the  packing  business 
became  concentrated,  the  large  amount  of  waste  matter  attracted 
attention.  This  resulted  in  the  conversion  of  animal  products 
that  were  not  fitted  for  food  or  for  manufacturing  purposes,  into 
fertilizing  material.  The  fertilizer  department  once  established, 
soon  led  to  the  study  of  the  utilization  of  all  by-products.  As- 
sisted by  Applied  Chemistry,  means  were  in  time  discovered  by 
which  every  available  part  of  the  animal  could  be  converted  into 
a  marketable  product.  The  value  of  using  waste  matter  which 
formerly  had  been  an  expense  to  remove  is  enormous.  It  has 
been  greatly  responsible  for  the  rapid  growth  and  development 
of  the  industry. 

The  large  modern  packing  houses  consist  of  many  departments, 
where  frequently  the  by-products  are  elaborated  to  the  finished 
articles,  so  that  they  go  direct  to  the  consumer  from  the  packer  ; 
thus  we  find  the  high  grades  of  fat  being  manufactured  into 
butterine  in  one  department,  lower  grades  into  soap  in  another 
department.  The  meat  canning  industry  and  the  manufacture 
of  such  products  as  beef-extracts,  pepsin,  sausages,  gelatin,  glue, 
lard,  sheep  skins,  feathers  and  many  articles  too  numerous  to 
mention,  are  now  frequently  part  of  the  packing  industry. 

Processes  in  the  Packing  House. — Inspection  and  Slaughtering. 
On  the  arrival  of  cattle,  sheep  or  swine  at  the  stockyards,  an 
inspection  is  made  by  a  representative  of  the  government  and 
where  pathogenic  conditions  are  suspected,  the  animal  is  seg- 
regated and  handled  separately.  A  post-mortem  inspection  is  also 
made  on  all  animals  and  on  all  parts  of  animals,  to  be  utilized  as 
food  (Fig.  51). 

As  a  rule,  animals  found  to  be  healthy  are  not  slaughtered  until 
the  day  after  their  arrival  at  the  packing  house,  thus  avoiding 
any  abnormal  conditions  such  as'  over  excitement  and  fatigue. 


FOOD    INDUSTRIES 


203 


After  slaughtering  they  are  bled  and  the  hide,  head,  feet  and 
internal  organs  are  removed.  They  are  then  scrubbed  and 
washed  in  each  part,  after  which  they  are  removed  to  the  cooler, 
where  they  hang  until  ready  for  shipment  or  until  they  are  sent 
to  the  cutting  room  for  curing,  sausage  making  or  canning. 

Beef  are  hung  far  enough  apart  to  admit  free  circulation  of 
air   and  the  temperature   is   dropped  as   quickly   as   possible   to 


Fig.  51.— Beef  Viscera  Inspection.     (Courtesy  of  Armour  &  Co.,  Chicago,  111.) 

40° -45°  F.  where  it  is  maintained  for  twelve  hours,  after  which 
it  is  gradually  dropped  to  34°-35°  F.  The  temperature  is  seldom 
allowed  to  fall  to  the  freezing  point. 

Hides,  Pelts  and  Bristles. — As  the  hide  of  beef  constitutes  the 
most  valuable  by-product,  great  care  is  given  to  the  handling 
and  curing,  preparatory  to  delivery  to  the  tanner.  It  is  removed 


2O4 


FOOD   INDUSTRIES 


from  the  freshly  killed  animals,  by  skilful  workmen,  freed  from 
adhering  flesh  and  fat  and  quickly  cooled.  A  combination  of 
fine  salt  and  rock  salt  which  has  been  crushed  and  screened,  is 
spread  over  each  hide  and  they  are  piled  one  above  the  other. 
During  the  curing  process,  which  lasts  for  25-30  days,  more  or 
less  of  shrinkage  takes  place,  after  which  the  salt  is  removed  and 
they  are  prepared  for  shipment. 

The  pelts  of  sheep  are  also  removed  after  slaughter.  When 
not  disposed  of  while  fresh,  they  are  cured  by  salting  and  some- 
times treated  so  that  the  wool  can  be  easily  removed  from  the 
skin. 

After  the  slaughter  and  scalding  of  swine,  the  bristles  are  taken 
from  the  back  and  ham  and  are  cured  first  by  drying,  either  in 
the  sun  or  with  artificial  heat  and  then  by  salting  They  are  used 
for  the  manufacture  of  brushes  or  made  into  curled  hair  for 
stuffing  mattresses,  cushions  and  similar  articles.  At  the  present 
time,  the  best  bristles  are  being  obtained  from  Russia  and  China. 

Fat. — The  second  important  by-product  is  fat,  which  is  ex- 
tensively used  for  the  manufacture  of  edible  products  and  many 
useful  articles.  From  the  bullock,  three  grades  of  fat  are  ob- 
tained. The  first  grade  yields  oleo  stock  from  which,  by  further 
treatment,  oleo  oil  and  oleo  stearin  are  obtained.  The  latter  prod- 
uct is  largely  used  in  the  preparation  of  compound  lard.  Oleo 
stock  is  frequently  called  butter-fat  as  oleo  oil  is  one  of  the  chief 
constituents  of  butterine.  Oleo  oil  may  be  sent  to  a  separate  de- 
partment of  the  packing  house  to  be  made  into  artificial  butter, 
or  as  raw  material,  it  may  be  sold  to  the  manufacturer  of  butter- 
ine. For  this  purpose,  large  quantities  are  shipped  abroad,  the 
greater  part  going  to  Holland  from  which  place  it  is  distributed 
to  other  European  countries. 

A  high  grade  of  fat  may  also  be  rendered  for  edible  tallow. 
This  was  the  type  fat  used  originally  in  the  manufacture  of  oleo- 
margarine. For  the  manufacture  of  artificial  butter  see  Chapter 
XIII.  A  second  grade  of  fat  is  rendered  for  ordinary  tallow 
which  may  be  further  separated  into  tallow  oil  and  tallow  stearin. 
Several  grades  of  tallow  are  known.  They  may  be  used  in  soap 


FOOD   INDUSTRIES 


205 


making,  candle  manufacture  and  in  the  preparation  of  glycerine, 
oleic  and  stearic  acids.  Tallow  may  be  utilized  for  lubricating 
purposes,  being  generally  compounded  with  other  material. 

From  the  sheep,  tallow  may  also  be  obtained.  It  is  hard  and 
white  in  appearance  and  is  known  as  mutton  tallow. 

One  of  the  most  important  factors  in  the  packing  house  is  the 
rendering  of  the  fat  from  hogs.  Several  grades,  prepared  by 


Fig.  52.— I^ard  Boiling.     (Courtesy  of  Armour  &  Co.,  Chicago,  111.) 

different  processes,  are  placed  upon  the  market,  known  as  kettle 
rendered  lard,  prime  steam  lard,  refined  lard  and  compound  lard. 
The  last  named  product  is  a  substitute  for  lard  and  consists 
largely  of  cotton  seed  oil,  oleo  stearin  and  tallow.  Kettle  rendered 
lard  is  the  highest  grade  of  household  lard.  It  is  generally  sup- 
posed to  be  made  entirely  from  leaf  lard,  but  only  two-thirds 
leaf  lard  is  used  as  a  rule,  the  remaining  amount  being  fat  taken 
from  the  back.  Neutral  lard  is  made  principally  from  leaf  lard 
but  by  a  more  complex  process  (Fig.  52). 


2C)6  FOOD    INDUSTRIES 

The  Feet. — From  the  feet  of  salughtered  animals,  a  valuable 
oil  known  as  neats-foot  oil  may  be  obtained.  The  bones  are 
sawed,  separated  from  the  hoofs,  washed  to  free  them  from 
blood  and  subjected  to  live  steam.  During  this  process,  the  bones 
fall  apart  and  the  oil  separates  out.  The  bones  may  be  ground 
into  meal  and  the  liquid  containing  dissolved  protein  may  be 
utilized  for  the  manufacture  of  glue.  The  oil  which  is  drawn 
off  is  refined  and  used  largely  for  leather  dressing. 

Bone  Products. — From  the  bones  of  the  head  and  feet  many 
useful  products  may  be  obtained.  One  of  the  most  valuable  is 
bone-black,  which  is  largely  used  in  the  industries  for  decoloriz- 
ing, as  in  the  bleaching  of  sugar,  glucose  and  similar  products. 
A  black  pigment  may  be  secured  also,  and  used  as  a  pigment  for 
paints  and  shoe  blackings.  Some  bones  are  ground  and  used  for 
fertilizing  purposes  while  others  are  worked  up  into  fancy  articles 
such  as  knife  handles,  buttons,  combs,  fans  and  many  similar 
products. 

Tankage. — Tankage  is  the  name  given  to  the  residue  which 
remains  in  the  tanks  where  meat  scraps  have  been  rendered  to 
separate  out  the  fat.  In  former  years,  it  was  always  considered 
waste  material  and  was  thrown  away.  The  operation  consists 
in  boiling  down  the  meat  scraps,  under  pressure  in  a  closed  tank 
or  "digester,"  for  several  hours.  After  all  the  parts  are  thor- 
oughly disintegrated  from  the  effect  of  the  high  temperature, 
the  fatty  matter  separates  out  and  can  be  withdrawn  through 
outlet  pipes  and  by  the  process  of  skimming.  The  material  which 
remains  in  the  vats  is  passed  through  filter  cloth  and  pressed, 
until  most  of  the  water  and  any  remaining  fat  are  removed.  It 
is  then  dried,  screened,  and  used  as  fertilizer  base.  The  com- 
mercial value  depends  on  the  amount  of  ammonia  and  bone- 
phosphate  which  it  contains.  As  the  tank  water  is  very  rich  in 
material  which  contains  ammonia,  it  is  concentrated  to  a  syrupy 
consistency  in  a  vacuum  pan,  mixed  with  copperas  and  dried. 
It  is  known  as  "concentrated  tankage"  and  is  used  for  mixing 
with  low  grade  tankage  to  increase  the  percentage  of  ammonia. 

Blood. — The  blood  which  flows  from  the  slaughtered  animals 


FOOD    INDUSTRIES 

is  conducted  through  drains  to  large  vats  or  receptacles,  care 
being  given  to  keep  it  free  from  all  foreign  matter,  such  as 
refuse,  manure  and  water.  It  is  then  cooked  by  live  steam  until 
the  albumin  has  coagulated,  after  which  it  is  pressed  and  dried. 
Dried  albumin  may  be  ground  and  screened  if  desired.  Albumin 
is  used  extensively  as  a  fertilizer  and  in  the  textile  industry  in 
setting  the  color  permanently  in  such  material  as  gingham.  The 
drained  blood  is  sometimes  used  in  beet  sugar  refining  as  a  clari- 
fying agent ;  it  is  then  known  as  "sugar  house  albumin." 

Mixing  Fertilisers. — To  make  a  complete  fertilizer,  phosphoric 
acid,  ammonia  and  potash  must  all  be  present.  As  only  ammonia 
and  phosphorus  compounds  are  obtained  from  bones,  tankage 
and  blood,  it  is  necessary  to  add  a  potassium  salt,  such  as  potas- 
sium chloride  or  sulphate.  According  to  need,  they  are  mixed 
in  different  proportions,  and  are  thoroughly  incorporated  with  a 
filler  as  earth  or  ashes  which  acts  as  a  diluent,  the  fertilizer 
when  used  alone  being  too  strong  for  plant  life. 

Glue  and  Gelatin. — Glue  and  gelatin  can  be  made  from  many 
by-products  of  the  packing  industry.  The  chief  sources  are  the 
liquids  in  which  have  been  boiled  cattle  and  sheep's  heads,  feet, 
bones,  sinews,  hide  trimmings,  calves'  heads  and  pigs'  feet.  Many 
grades  may  be  obtained  from  fine  white  gelatin  to  a  low  grade 
dark  appearing  glue,  according  to  the  part  of  the  animal  used, 
the  condition  of  the  raw  material  and  the  care  in  manufacture. 
In  order  to  produce  a  high  grade  product,  careful  attention  must 
be  given  to  the  raw  material  in  order  that  decomposition  does 
not  set  in.  Only  that  which  is  in  a  sound,  sweet  condition  should 
be  utilized.  It  is  also  essential  that  a  low  temperature  be  used 
in  concentrating  the  glue  liquor,  so  that  scorching  may  be  pre- 
vented and  undesirable  changes  may  not  take  place.  This  is 
accomplished  by  evaporating  the  liquid,  to  the  desired  density, 
in  a  vacuum  pan  from  which  it  is  run  into  molds,  chilled  and 
clarified.  It  is  then  cut  into  layers  and  dried  in  an  oven. 

In  order  to  dissolve  the  mineral  matter,  bones  are  frequently 
leached  with  an  acid.  By  allowing  them  to  remain  in  dilute 
hydrochloric  (2°  Be.)  or  phosphoric  (6°  Be.)  for  three  or  four 


2O8  FOOD   INDUSTRIES 

weeks,  the  bones  become  soft  and  spongy.  They  are  then  freed 
from  the  acid  by  careful  washing,  after  which  they  are  converted 
into  gelatin. 

Bleaching  the  bones  before  cooking  the  glue  liquid  is  practiced 
by  many  manufacturers.  Sulphur  dioxide  is  most  frequently 
used,  although  other  bleaching  agents  may  be  employed,  such  as 
zinc  sulphate  or  chloride  and  peroxide  of  hydrogen.  In  addition 
to  bleaching  these  agents  act  as  preservatives,  thus  preventing 
decomposition  from  setting  in.  Formaldehyde  is  also  used  in 
small  quantities  as  a  preservative. 

Canning  of  Meat,  Beef  Extracts,  Sausages,  etc. — As  a  rule 
the  canning  of  meat  is  carried  on  as  a  separate  industry.  -See 
Chapter  XIX.  It  is,  however,  one  of  the  side  issues  that  is  fre- 
quently found  in  the  packing  house,  being  established  with  the 
view  of  saving  a  large  proportion  of  meat  that  would  otherwise 
be  wasted,  or  would  be  sold  at  a  very  low  price.  In  this  way 
many  of  the  cheaper  cuts  of  meat,  which  are  nourishing  and 
healthy,  can  be  utilized.  The  preservation  of  meat  by  hermet- 
ically sealing,  has  led  to  still  another  department  within  the 
packing  house.  In  the  soaking  and  cooking  of  meat,  part  of  the 
water-soluble  constituents  are  dissolved  out.  By  concentration 
in  a  vacuum  pan,  these  waste  liquors  together  with  the  bone 
liquid,  may  be  converted  into  beef  extracts.  Fresh  meat  is 
rarely  used  for  this  purpose  among  packers,  consequently  the 
cost  of  preparing  beef  extracts  by  them  is  very  small.  For 
manufacturing  processes,  see  Chapter  XIV. 

In  the  sausage  department,  the  packer  finds  another  way  of 
disposing  of  those  portions  of  meat  which  are  nutritious  but  not 
palatable  in  their  original  condition.  Sausages,  bologna,  frank- 
furts,  scrapple  and  similar  products  are  prepared  after  various 
formulae  and  placed  upon  the  market.  Besides  meat  from  differ- 
ent parts  of  the  beef  and  pork,  such  products  may  contain  corn 
flour,  cracker  meal,  boiled  potatoes,  starches  and  dextrins.  These 
are  frequently  spoken  of  as  "fillers"  and  serve  to  prevent  shrink- 
age in  bulk  under  the  influence  of  heat.  A  great  variety  of 
flavoring  agents  are  added,  such  as  sugar,  salt,  white  or  red 


FOOD   INDUSTRIES  2O9 

pepper,  cinnamon,  mace,  allspice,  cloves,  coriander,  carraway 
seeds,  marjortam  and  onions  or  garlic.  Salt-petre  and  color 
water,  consisting  of  dyes  of  various  kinds,  assist  in  giving  a 
better  appearance.  A  common  practice  still  exists  in  the  use  of 
borax  and  boracic  acid  for  purposes  of  preservation. 

The  manufacture  of  animal  casings  from  the  round  or  small 
guts,  middle  or  large  intestines  and  bladders,  of  cattle,  sheep 
and  hogs,  furnish  another  example  of  the  utilization  of  material 
entirely  lost  until  the  establishment  of  the  modern  packing  house. 
In  order  to  supply  the  demand,  artificial  casings  may  be  pre- 
pared from  cellulose,  to  take  the  place  of  animal  casings.  To 
improve  the  appearance  of  casings,  to  insure  against  shrinkage 
and  to  prevent  molding,  varnish  is  sometimes  used.  It  is  pre- 
pared from  shellac,  boracic  acid,  ammonia  and  water. 

There  is  probably  more  chance  for  deception  in  the  manufac- 
ture of  these  products  than  in  any  other  form  of  animal  food 
found  on  the  market.  When  properly  prepared,  they  are  highly 
prized  as  food  products.  The  frequent  use,  however,  of  such 
material  as  borax,  boracic  acid,  sulphite  of  soda,  undesirable 
colorings  and  excessive  quantities  of  filler,  is  making  the  inspec- 
tion of  factories  the  only  safeguard  that  the  consumer  has  for 
protection  against  the  adulteration  of  these  products. 

Minor  Packing  House  Products. — In  connection  with  the  pack- 
ing industry,  many  other  branches  may  be  found,  such  as  the 
manufacture  of  chipped  dried  beef,  the  curing  and  smoking  of 
tongues  and  hams,  and  the  preparation  of  pharmaceutical  prod- 
ucts from  the  various  organs  of  slaughtered  animals.  From  the 
mucous  membrane  of  the  stomach  of  hogs,  pepsin  is  made  and 
a  similar  ferment  known  as  pancreatin  may  be  obtained  from 
the  pancreas  or  sweetbreads  of  animals. 

In  a  like  manner,  from  the  bullock  may  be  extracted  cardine 
from  the  heart,  medulline  from  the  spinal  cord,  musculine  from 
the  muscular  tissues  and  cerebrine  from  the  brain.  The  thyroid 
glands  of  the  sheep  and  the  bullock  yield  thyroidine.  It  is 
claimed  that  these  extracts  from  animals  are  beneficial  in  the 
treatment  of  diseases  of  human  organs  similar  to  those  from 
which  the  extracts  are  prepared. 


CHAPTER  XVI. 


MILK. 


Fig-  53- — Burnside  Kami,  N.  Y. 

Source. — Milk  is  a  white  opaque  fluid  which  is  secreted  by  the 
lacteal  glands  of  the  female  of  all  animals,  which  belong  to  the 
mammalian  class.  It  is  intended  by  nature  to  supply  nourish- 
ment to  the  young,  until  such  a  time  as  it  is  able  to  take  food 
similar  to  that  utilized  by  the  parents. 

In  different  parts  of  the  world  various  animals  are  bred  for 
the  purpose  of  producing  milk  for  the  use  of  mankind.  Prob- 
ably the  goat  was  one  of  the  first  animals  to  supply  milk  to  the 
human  family,  and  in  the  rough,  hilly  districts  of  Europe,  espe- 
cially in  the  Swiss  Alps,  it  is  still  very  common.  The  milk  of  the 
buffalo,  the  camel,  the  mare  and  the  reindeer  is  frequently  used, 
while  in  parts  of  Europe  the  ewe  has  produced  much  milk  for  the 
manufacture  of  cheese. 

History  does  not  tells  us  how  the  cow  came  to  be  developed 
as  a  producer  of  milk,  but  in  most  civilized  countries  where  the 
climatic  conditions  permit,  cow's  milk  is  almost  entirely  used. 
It  is  not  more  desirable  for  human  food  than  the  milk  of  other 
animals,  but  in  her  development  the  cow  has  shown  herself  to 


FOOD   INDUSTRIES  211 

be  able  to  give  the  best  return  for  a  given  amount  of  care  and 
feeding. 

Composition. — Chemically  milk  is  composed  of  all  the  essentials 
necessary  to  sustain  life  for  a  long  period  and  is,  therefore,  fre- 
quently spoken  of  as  a  perfect  food.  It  can  only  be  regarded  in 
this  light,  however,,  when  utilized  by  the  type  of  animal  for 
which  it  is  intended. 

The  composition  varies  in  different  animals,  even  in  animals 
of  the  same  species,  but  the  difference  is  rather  in  the  relative 
proportion  of  the  various  constituents,  than  in  the  general  prop- 
erties and  composition  of  the  ingredients  themselves.  The  fol- 
lowing figures  will  give  a  general  idea  of  the  composition  of 
cow's  milk,  although  a  great  variation  may  occur  according  to 
the  breed,  age  of  cow,  period  of  lactation,  amount  and  character 
of  the  food,  etc. 

Per  cent. 

Water 87.2 

Total  Solids 12.8 

Fat   3.6 

Carbohydrate 4.9 

Protein 3. 3 

Mineral  matter 0.7 

Water  is  the  largest  constituent  of  the  milk,  containing  in  solu- 
tion, semi-solution  or  in  suspension,  the  remaining  ingredients 
which  are  known  as  the  total  solids.  Of  these  total  solids,  fat  is 
commercially  the  most  important  as  it  is  the  source  of  butter 
and  to  a  great  extent  cheese.  The  amount  differs  more  than  any 
other  constituent,  being  low  in  the  Holstein  and  relatively  high 
in  the  Jersey  and  Guernsey.  The  average  should  not  fall  below 
3  per  cent,  and  except  in  very  rich  milk,  it  will  not  exceed  5  per 
cent. 

Fat  occurs  in  milk  as  an  emulsion,  suspended  in  the  milk 
serum  in  the  form  of  globules.  On  account  of  their  specific 
gravity  these  globules  rise  more  or  less  readily  to  the  top,  when 
milk  is  allowed  to  remain  at  rest,  and  are  then  known  as  cream 
or  top  milk. 

Chemically,  the  fat  which  is  known  as  butter-fat  exists  in  two 


212  FOOD   INDUSTRIES 

J 

forms,  non-volatile  and  volatile.  The  non-volatile  or  insoluble 
fats  make  up  about  90  per  cent,  of  the  total  amount,  and  consist 
of  a  number  of  fats  of  which  palmitin,  olein  and  stearin  are  the 
most  important.  The  characteristic  taste  and  odor  of  milk  and 
butter  are  largely  due  to  the  existence  of  certain  volatile  fats, 
butyrin,  caprin,  caproin  and  caprilin  which  constitute  the  re- 
maining 10  per  cent.  Of  these  butyrin  is  the  most  important. 
It  occurs  in  the  largest  proportion  and  is  the  fat  which  on  de- 
composing yields  butyric  acid,  readily  detected  in  rancid  butter. 

The  carbohydrate  in  milk  is  known  as  lactose  or  milk  sugar. 
It  belongs  to  the  disaccharid  group  as  do  sucrose  and  maltose, 
and  is  similar  so  far  as  its  ultimate  composition  is  concerned. 
The  most  marked  difference  is  solubility;  sucrose  and  maltose 
are  very  readily  soluble  in  water  while  lactose  dissolves  with 
difficulty.  Milk  sugar,  therefore,  does  not  possess  the  sweeten- 
ing power  of  the  other  disaccharids  and  is  not  apt  to  pall  upon 
the  taste  so  rapidly. 

Lactose  does  not  readily  yield  to  yeast  fermentation,  but  under 
the  influence  of  certain  bacteria  found  in  all  normal  milk,  it 
undergoes  partial  decomposition  yielding  lactic  acid  according 
to  the  following  formulae : 

Cn  H22On>  H2O  —  4CH3  CHOH  COOH. 

This  change  begins  in  the  milk  as  a  rule  almost  immediately 
after  it  is  drawn  from  the  cow  and  continues  until  0.9  of  I  per 
cent,  is  formed,  when  further  decomposition  is  checked  by  the 
lactic  acid. 

The  chief  protein  of  milk  is  caseinogen  which  exists  in  an 
extremely  fine  colloidal  state  in  intimate  contact  with  calcium 
phosphate.  Caseinogen  will  not  coagulate  on  heating,  but  when 
subjected  to  an  acid  which  combines  readily  with  the  calcium, 
it  will  precipitate  out  of  the  solution  in  the  form  of  a  curd.  It 
is  very  important  commercially  as  it  is  one  of  the  chief  constit- 
uents of  cheese.  Albumin  and  globulin  also  occur  in  solution  in 
milk  but  in  relatively  small  amounts,  approximately  0.5  of  I 
per  cent,  of  the  total  protein.  They  are  essentially  the  same  in 


FOOD   INDUSTRIES  213 

chemical  composition  as  the  albumin  and  globulin  found  in  blood 
and  egg. 

Mineral  matter  is  present  in  a  relatively  large  amount,  0.7  of 
I  per  cent,  in  cow's  milk  and  is  utilized  mainly  for  building  pur- 
poses. Small  amounts  of  a  variety  of  salts  occur — phosphate 
of  lime  and  potash,  chlorides  and  sulphates  of  sodium  and  potas- 
sium, with  very  small  amounts  of  iron  and  magnesium.  Human 
milk  contains  much  less  inorganic  matter,  approximately  0.2 
per  cent,  being  present.  It  is  frequently  necessary,  therefore,  in 
infant  feeding  to  modify  milk  so  it  will  more  closely  resemble 
mother's  milk. 

Milk  contains  several  other  constituents  occurring  in  minute 
quantities.  Lime  occurs  in  combination  with  citric  acid  in  the 
form  of  a  salt  known  as  citrate  of  lime.  It  is  also  rich  in  various 
enzymes  which  assist  in  the  digestion  of  the  protein,  fat  and  milk 
sugar.  For  a  short  period  after  it  has  been  drawn,  bactericidal 
bodies  are  present.  The  characteristic  color  of  the  fluid  is 
largely  due  to  lactochrome,  which  occurs  in  varying  amounts, 
and  is  generally  supposed  to  be  intimately  associated  with  the 
palmitin. 

IMPORTANCE  OF  THE  MILK  SUPPLY. 

Of  all  our  standard  articles  of  food  none  have  received  as 
much  attention  as  the  production  and  handling  of  milk.  The 
reason  for  this  may  readily  be  seen,  for  it  has  been  found  that 
milk  is  more  apt  to  be  dangerous  to  health  than  any  common 
food  product.  It  deteriorates  very  rapidly  and  as  it  is  usually 
taken  in  the  raw  state,  no  protection  is  afforded  the  consumer 
through  the  process  of  cooking.  The  fact  that  it  forms  the  sole 
diet  of  the  human  being  at  an  immature  age  makes  this  problem 
a  very  serious  one.  Should  there  be  any  contamination,  the 
child  would  be  liable  to  take  it  when  least  able  to  cope  with  a 
disease. 

Besides  the  chemical  compounds  previously  considered,  milk 
contains  a  large  number  of  bacteria  which  gain  access  to  it  after 
it  is  secreted.  Unfortunately  the  warmth  of  the  milk,  its  fluid 
condition  and  its  composition  make  it  a  most  favorable  medium 


BACTERIAI/TESTS 

OF 

CREAMERY  MILK 


5,000,000 

B/*CTERIA 
PER   CC 


FARMERS   MILK 

DELIVERED 
TO  CREAMERY 


6,700 

BACTERIA 
PER  CC 


SAME  MILK  AFTER 
PASTEURIZING  iMIN. 
AT  155'F. 


560,000 

BACTERIA 
PER   C.C. 


SAME  MILK  AFTER 

5  MINUTES  IN 
CREAMERY  Ml  K  CANS 


1.270.000 

BACTERIA 
PER   CC 


WATER  IN  WHICH 
MILK  CANS  RECEIVE 
FINAL  RINSING 


90.000.000 

BACTERIA 
PER  CUBIC 
CENTIMETER 


MILK    FROM   SAME 

CANS  AFTER  ARRIVAL 

IN  NEW  YORK  CITY 

NEXT  MORNING 


CARELESS  HANDLING 


BACTERIA  COUNTS  TELL  THE  STORY  OF  UNSANITARY  CONDITIONS 

Fig.  54- 


BAG  T  ERI  AtTESTS 


CREAMERY  MILK 


28,000 

BACTERIA 
PER  C.C. 


FARMER'S  MILK 

DELIVERED 
TO  CREAMERY 


SAME  MILK  AFTER 
PASTEURIZING  30  WIN. 
AT    145'  F 


3.000 

BACTERIA 
PER    C.C. 


SAME  MILK  AFTER 

3    MINUTES    IN 

CREAMERY  BOTTLES 


NO 
BACTERIA 


WATER  IN   WHICH 

BOTTLES  RECEIVE 

FINAL  RINSING 


5.000 

BACTERIA 

PER   CUBIC 

CENTIMETER 


MILK  FROM    SAME 
BOTTLES  AFTER 
ARRIVAL  I NN.Y. CITY 
NEXT   MORNING 


CAREFUL 


HANDLING 


BACTERIA  COUNTS  TELL  THE  STORY  OF  SANITARY  CONDITIONS 

Fig-  55- 


2l6  FOOD   INDUSTRIES 

for  the  growth  of  these  micro-organisms.  They  reproduce  very 
rapidly  and  unless  precautions  are  taken  to  inhibit  their  increase, 
the  number  becomes  enormously  large  in  a  comparatively  short 
time  (Figs.  54-55).  Through  their  action,  changes  begin  to 
take  place  in  the  milk  constituents  and  in  time  decomposition 
advances  so  far,  that  the  milk  is  no  longer  fit  for  consumption. 

Diseases  from  Milk. — The  greater  number  of  the  germs  in  milk 
are  harmless  excepting  the  germs  of  specific  diseases  as  tuber- 
culosis, typhoid,  scarlet  fever,  diphtheria  and  septic  sore  throat. 
The  most  dreaded  disease  is  that  of  tuberculosis.  The  bacilli 
may  come  directly  from  the  cow  affected  with  bovine  tuber- 
culosis, in  which  case  there  is  a  possibility  of  large  numbers  be- 
ing present  in  the  milk  when  it  is  drawn  from  the  teats.  Such 
milk  when  mixed  with  that  drawn  from  other  cows,  may  con- 
taminate the  supply  from  the  entire  herd.  Expert  examination 
has  proved  that  the  disease  is  as  prevalent  among  cows  as  it  is 
in  the  human  family  especially  when  the  animal  has  been  kept 
under  bad  hygienic  conditions.  Rosenau  states*  "The  fact  that 
bovine  tuberculosis  is  frequently  fatal,  especially  in  children, 
may  be  divined  from  the  fact  that  fifteen  per  cent,  of  the  fatal 
cases  of  tuberculosis  in  children  under  five  year  of  age  that  have 
been  studied,  were  due  to  the  bovine  type  of  bacillus"  and  "from 
five  to  seven  per  cent,  of  all  human  tuberculosis  is  ascribed  to 
infection  with  the  bovine  bacillus."  This  shows  the  importance 
of  the  care  which  should  be  given  in  the  milch  cow  and  the 
necessity  of  making  the  tuberculin  test  from  time  to  time. 

Milk  may  also  be  contaminated  from  persons  having  pulmonary 
tuberculosis  or  through  the  contaminated  cloths  or  insanitary 
actions  of  the  milker.  It  is  believed  that  epidemics  of  diphtheria 
and  scarlet  fever  have  been  caused  by  the  milk  supply,  probably 
through  secondary  infection.  The  great  importance  of  the 
health  and  cleanliness  of  the  milker  and  his  family  is  again 
shown  in  typhoid,  since  the  cow  does  not  have  that  disease.  An 
impure  water  supply  in  which  milking  utensils  are  washed  has 
frequently  been  the  cause  of  the  spread  of  typhoid.  For  this 

*  Rosenau — The  Milk  Question,  p.  100. 


FOOD   INDUSTRIES  21 7 

reason  no  water  which  is  not  above  suspicion  should  be  used 
about  the  dairy,  for  either  drinking  or  washing  purposes.  In 
recent  years,  pathogenic  streptococci  causing  sore  throat  have 
been  traced  to  infected  milk. 

Cholera  infantum  is  believed  by  some  authorities  to  be  due  to 
the  abnormal  increase  of  bacteria  of  filth,  rather  than  to  any  one 
species  of  micro-organism.  That  it  is  due  to  milk  bacteria  has 
been  proved  by  the  fact  that  the  trouble  occurs  in  greatest 
abundance  at  the  season  of  the  year  when  milk  bacteria  are  most 
numerous ;  that  it  is  chiefly  confined  to  infants  fed  upon  cow's 
milk  and  that  the  disease  is  greatly  reduced  when  care  is  given 
to  supply  pure  milk. 

Necessity  for  Cleanliness. — Since  milk  may  so  easily  become 
contaminated,  since  it  is  a  favorite  medium  for  the  development 
of  bacteria  and  must  so  frequently  be  carried  a  long  distance, 
cleanliness  is  an  absolute  necessity  in  the  production  and  handling 
of  our  milk  supply.  Means  should  also  be  taken  to  prevent 
the  growth  of  micro-organisms,  for  even  when  produced  under 
sanitary  conditions,  bacteria  in  small  numbers  are  always  present. 
Their  development  may  be  inhibited  by  dropping  the  tempera- 
ture immediately  after  milking  to  50°  F.  and  maintaining  this 
temperature  until  the  milk  is  delivered.  The  importance  of  per- 
fect cleanliness  and  low  temperature  cannot  be  over-estimated. 

Safeguarding  the  Milk  Supply. — To  safeguard  the  supply,  laws 
have  been  passed  by  the  city  and  state  governments,  which  while 
differing  in  detail,  contain  the  same  general  rules.  As  regards 
composition  milk  must  not  contain  more  than  87-88  per  cent, 
water  and  should  contain  12-13  per  cent,  total  solids  of  which 
3  per  cent,  should  be  fat.  It  must  be  guarded  from  producer  to 
consumer,  by  surrounding  it  with  sanitary  conditions  and  a  tem- 
perature sufficiently  low  to  prevent  growth  of  micro-organisms. 
No  preservative,  such  as  borax,  boracic  acid,  salicylic  acid  or 
formaldehyde  should  be  used.  Some  cities  also  have  a  law  in 
regard  to  the  bacterial  count,  but  this  has  been  found  imprac- 
ticable in  large  communities. 

Because  of  its  wide  usage  as  a  food,  milk  is  more  closely 


2l8  FOOD    INDUSTRIES 

supervised  than  other  articles  in  the  diet.  It  is  inspected  at  the 
farm,  at  creameries,  during  transportation,  at  receiving  stations 
and  in  distributing  centers.  Regulations  are  now  more  or  less 
enforced  affecting  surroundings  where  milk  is  produced.  The 
water  supply  must  be  above  suspicion.  The  utensils  should  be 
heavily  tinned  and  seamless.  They  should  be  subjected  each  day 
to  a  thorough  washing  and  if  possible  to  live  steam  or  exposure 
to  sunlight.  The  stables  should  be  light,  well  ventilated  and  fre- 
quently whitewashed.  No  utensils,  feed  or  other  animals  should 
be  kept  in  the  stables.  Bedding  and  manure  must  be  daily 
removed.  The  cow  should  be  healthy  and  kept  as  clean  as  pos- 
sible. The  milker  and  dairyman's  family  should  be  free  from 
contagious  disease.  The  milk  should  be  drawn  through  a  small 
mouthed  sanitary  milk  pail,  strained  and  cooled  immediately. 

During  the  journey  to  the  consumer  milk  should  be  kept  out 
of  contact  with  air  and  should  be  iced.  Sanitary  conditions 
should  also  prevail  where  it  is  distributed.  Although  the  state 
may  control  more  or  less  the  supply  of  milk  from  the  producer 
to  the  consumer,  once  in  the  hands  of  the  housekeeper,  the  law 
is  powerless  to  control  the  handling  of  milk.  Too  frequently 
through  ignorance  or  utter  carelessness,  milk  which  has  been 
carefully  handled  by  farmer  and  distributor  is  ruined  by  the 
housewife.  It  is  as  much  her  duty  to  see  that  milk  is  guarded 
carefully  as  it  is  of  those  who  have  handled  it  before  her.  The 
following  hints  to  housekeepers  have  been  contributed  by  some 
of  the  students  of  Teachers  College:  Buy  for  daily  use;  buy 
bottled  milk  whenever  possible;  when  milk  must  be  bought  from 
an  open  can,  use  a  covered  receptacle  to  put  it  in,  as  a  glass  fruit 
jar;  do  not  transfer  bottled  milk  to  another  receptacle;  on  receiv- 
ing, wash  the  top  and  outside  of  the  bottle  thoroughly  and  place 
at  once  near  the  ice  in  the  ice-box ;  do  not  mix  old  and  new  milk ; 
»  since  milk  absorbs  odors,  do  not  put  strong  smelling  food  near 
it ;  keep  well  covered  at  all  times ;  when  the  bottle  is  empty,  rinse 
with  cold  water,  wash  thoroughly  with  hot  water  and  set  to  drain 
away  from  dust ;  do  not  use  milk  bottles  for  any  other  purpose ; 
if  there  is  a  contagious  disease  in  the  family,  until  the  danger  is 


FOOD   INDUSTRIES  219 

over,  place  a  clean  covered  container  where  the  milkman  may 
pour  the  contents  of  the  milk  bottle  which  he  is  delivering  into 
the  container,  or  keep  all  bottles  delivered  during  the  period  of 
illness  before  returning,  at  which  time  they  should  be  thoroughly 
sterilized;  general  rule — keep  milk  cold  and  free  from  dirt. 

Our  Duty  to  the  Producer. — As  the  study  of  the  milk  problem 
advances,  more  and  more  has  been  required  of  the  producer. 
The  law  now  demands  that  cows  must  be  in  a  healthy  condition, 
that  old  barns  and  surroundings  must  be  cleaned  or  new  barns 
built,  stables  must  be  whitewashed,  the  water  supply  must  be 
examined,  new  utensils  must  be  bought  and  more  care  must  be 
given  to  cleanliness,  which  means  more  labor  at  an  additional 
cost.  These  requirements  have  greatly  added  to  the  cost  of  the 
production  of  milk,  and  the  farmer  can  no  longer  supply  milk 
at  a  profit  for  the  same  price  as  when  insanitary  conditions  pre- 
vailed. The  advance  in  price  should,  therefore,  be  cheerfully 
borne  by  the  consumer  who  is  receiving  a  far  better  product 
to-day  than  in  years  gone  by. 

Testing-  of  Milk. — Milk  is  usually  tested  by  the  lactometer 
which  registers  the  specific  gravity,  and  by  the  Babcock  test  which 
gives  the  percentage  of  fat  and  also  assists  in  the  detection  of 
formaldehyde.  The  estimate  of  the  amount  of  water  and  total 
solids  is  made  together  with  the  bacterial  count.  For  further 
information  in  regard  to  these  tests  see  a  standard  work  on  milk 
as  Milk  and  Its  Products  by  Wing,  The  Production  and  Handling 
of  Clean  Milk  by  Winslow,  Harrington's  Practical  Hygiene,  or 
Van  Slyke's  Methods  of  Testing  Milk  and  Milk  Products. 

Sterilization. — Even  with  ordinary  care  milk  contains  a  large 
number  of  bacteria  which  multiply  rapidly.  As  previously  seen 
they  may  be  a  harmless  type  or  those  of  specific  diseases.  These 
troubles  have  led  to  the  treatment  of  milk  by  heat,  the  oldest 
method  being  that  of  sterilization. 

As  sterilization  means  the  destruction  of  all  micro-organisms, 
it  is  necessary  either  to  hold  milk  at  a  temperature  of  248°  F.  for 
15  minutes  or  to  raise  it  to  the  boiling  temperature  on  three  suc- 
cessive days.  This  insures  not  only  the  destruction  of  bacteria 


220 


FOOD   INDUSTRIES 


ig-  56.— Pasteurization  of  Milk.  The  milk  passes  from  the  receiving  tank  ( A )  through 
the  clarifiers  (B)  to  the  pasteurizer  (C)  where  it  is  heated  to  145°  F.  It  is  then  con- 
ducted to  the  holding  tanks  (Fig.  57).  (Courtesy  of  the  Sheffield-Farms-Slawson- 
Decker  Co.) 


I^Fig.  57. — Holding  Tanks.  Milk  heated  to  145°  F.  is  conducted  successively  to  four 
holding  tanks  where  it  is  held  for  fifteen  minutes  in  each  tank.  At  a  temperature 
of  about  142°  F.  it  passes  back  through  the  pasteurizers  and  is  rapidly  cooled. 
(Courtesy  of  the  Sheffield-Farms-Slawson-Decker  Co.) 


FOOD   INDUSTRIES 


221 


Fig.  58. — Milk  Coolers.     (Courtesy  of  the  Sheffield-Farms-Slawson-Decker  Co.) 


59.— Milk  Bottling  Machine.      (Courtesy  of  the  Sheffield-Farms-Slawson-Decker  Co.) 


222  FOOD    INDUSTRIES 

but  spores  of  a  highly  resistant  type  and  renders  the  milk  practi- 
cally sterile.  If  air  be  excluded  such  milk  can  be  held  indefi- 
nitely. While  undoubtedly  this  is  the  most  effective  method  of 
protecting  milk  against  bacterial  decomposition,  it  unfortunately 
so  alters  the  composition  as  to  make  it  more  difficult  to  digest. 
This  has  proved  so  serious  an  objection  that  sterilization  has 
been  practically  abandoned  in  America,  and  either  pasteuriza- 
tion or  the  use  of  clean  raw  milk  has  taken  its  place. 

Pasteurization. — The  term  pasteurization  means  the  heating  of 
milk  below  the  boiling  point,  from  140°  to  160°  F.,  followed  by 
rapid  cooling  (Figs.  56-59).  This  method  was  named  from  Pasteur 
who  suggested  its  use  in  1864  for  the  preservation  of  beer  and 
wine.  It  was  not,  however,  until  1886  that  the  process  was  ap- 
plied to  milk.  It  differs  from  sterilization  mainly  in  the  degree 
of  heat  to  which  bacteria  are  subjected.  All  micro-organisms 
are  not  destroyed  by  this  method  so  pasteurized  milk  will  in  time 
decompose.  It  has  been  found,  nevertheless,  that  from  95  to  98 
per  cent,  of  bacterial  life  and  practically  all  of  disease  bacteria 
have  been  rendered  harmless,  so  milk  thus  treated  can  be  kept 
from  souring  from  twelve  to  twenty-four  hours  longer.  If  milk 
has  been  kept  for  a  period  before  pasteurization,  poisons  may 
have  been  formed  in  it  which  heat  will  not  destroy.  It  is,  there- 
fore, absolutely  essential  that  only  clean,  fresh  milk  should  be 
pasteurized.  The  process  can  in  no  way  take  the  place  of 
cleanliness  and  should  never  be  used  to  atone  for  insanitary 
methods  in  the  production  and  handling  of  the  milk  supply. 

If  a  low  temperature  has  been  used  pasteurizing  does  not 
injure  milk  so  far  as  its  nutritive  value  is  concerned  and  it  af- 
fords a  certain  protection  against  such  diseases  as  tuberculosis 
and  typhoid  which  have  been  previously  discussed. 

Certified  Milk. — The  term  is  intended  to  signify  that  the  milk 
is  certified  as  to  its  quality  and  wholesomeness  by  a  medical 
milk  commission1.  While  pasteurization  properly  carried  out  has 
greatly  assisted  in  safeguarding  the  milk  supply  of  large  cities, 
where  enormous  quantities  must  frequently  be  carried  long  dis- 
tances, it  is  by  no  means  ideal.  It  frequently  means  a  purified 


FOOD   INDUSTRIES  223 

rather  than  a  pure  milk.  This  has  proved  satisfactory  for  or- 
dinary household  purposes  and  for  adults,  but  in  infant  feeding 
nothing  can  take  the  place  of  pure  raw  milk  produced  under 
ideal  conditions.  A  standard  of  excellence  has  been  fixed  by 
medical  commissions  and  milk  which  can  satisfy  these  require- 
ments is  sold  under  the  name  of  certified  or  guaranteed  milk. 
The  bacterial  count  must  be  low,  and  it  must  possess  the  other 
characteristics  of  pure  wholesome  milk.  This  can  only  be  se- 
cured by  perfect  cleanliness  in  regard  to  the  dairy,  dairy  methods, 
care  of  the  cow,  and  health  of  the  milker.  To  comply  with 
sanitary  regulations  means  an  excess  cost  to  the  producer,  so 
certified  milk  may  be  sold  at  a  higher  price.  Such  milk  is  fre- 
quently sold  under  the  special  name  of  the  dairy,  as  Walker- 
Gordon  milk. 

Modified  Milk. — As  the  composition  of  cow's  milk  differs  from 
that  of  human  milk,  being  higher  in  protein  and  mineral  matter 
and  lower  in  milk  sugar,  it  is  frequently  found  necessary  to 
change  the  composition  of  cow's  milk  to  more  nearly  make  it 
resemble  that  of  the  human  being,  or  to  give  a  milk  of  known 
composition  especially  adopted  to  the  particular  needs  of  the 
infant  or  invalid.  Water,  barley  water,  lime  water  or  dextrin- 
ized  gruel  may  be  used  as  a  diluent  and  cream  and  milk  sugar 
may  or  may  not  be  added.  Such  a  product  is  called  modified 
milk. 

All  precautions  stated  above  for  the  production  and  handling 
of  clean  milk  as  well  as  the  requirements  of  the  certifying 
Medical  Society  should  be  observed  in  producing  modified  milk. 


CHAPTER  XVII. 


MILK  PRODUCTS. 

Condensed  Milk. — The  importance  of  milk  in  the  diet  and  its 
rapid  deterioration  even  under  the  most  favorable  conditions, 
have  led  to  much  experimentation  along  the  line  of  its  preserva- 
tion for  a  long  period. 

In  the  early  part  of  the  igih  century,  an  attempt  was  made 
to  hold  milk  indefinitely  by  reducing  the  percentage  of  water. 
As  a  high  temperature  was  used  in  the  condensing  process, 
the  result  was  a  boiled  milk,  the  composition  of  which  greatly 
differed  from  the  raw  material.  Lactose  like  any  other  sugar 
caramelized  in  time  and  gave  to  the  finished  product  a  dark 
color  and  a  bitter  tatse.  Lime  salts,  so  necessary  in  the  digestion 
of  milk,  were  thrown  out  of  solution  and  the  protein  matter  was 
much  altered  in  composition.  The  process  proved  a  failure. 

It  was  not  until  1856  that  another  attempt  was  made  to  pre- 
serve milk  by  condensing  it.  At  that  time  Gail  Borden  was 
granted  a  patent  "On  a  process  for  concentrating  milk  by  evapo- 
ration in  vacuo,  having  no  sugar  or  other  foreign  matter  mixed 
with  it."  This  early  process  reduced  the  temperature  to  160°  F. 
and  eventually  resulted  in  placing  a  satisfactory  product  on  the 
market.  Although  the  early  days  of  the  condensed  milk  business 
were  full  of  discouragement  to  the  manufacturer,  the  industry 
has  now  grown  to  enormous  proportion,  rapid  strides  having 
been  made  during  the  past  ten  years.  This  shows  the  rapid 
increase  in  the  consumption  of  condensed  milk  not  only  in  coun- 
tries where  the  breeding  of  the  cow  is  impossible,  but  also  for 
use  on  ocean  liners,  in  the  navy,  lumber  and  mining  camps  and 
in  home  markets. 

The  successful  condensing  of  milk  requires  that  the  raw 
material  be  produced  under  the  best  hygienic  surroundings,  and 
invariably  the  dairy  conditions  will  be  found  to  be  in  a  high 
state  of  development,  wherever  milk  is  being  produced  for  the 
condensing  industry. 


FOOD    INDUSTRIES 


225 


226  FOOD   INDUSTRIES 

There  are  two  classes  of  condensed  milk,  sweetened  and 
unsweetened. 

Process. — When  milk  is  received  at  the  factory  it  is  tested, 
filtered  to  remove  dirt,  and  immediately  sterilized  by  raising  the 
temperature  of  the  milk  to  the  boiling  point.  Sugar  is  added  to 
the  extent  of  about  16  pounds  to  100  pounds  of  milk.  The 
sweetened  fluid  is  run  into  a  vacuum  pan  and  kept  at  a  tempera- 
ture of  approximately  130°  F.  until  it  is  condensed  about  two 
and  one-half  times.  When  sufficiently  concentrated  it  is  run  into 
40  quart  cans  which  are  surrounded  by  ice.  During  this  opera- 
tion which  lasts  one  hour,  the  milk  is  constantly  stirred  with 
paddles  after  which  it  is  immediately  run  into  tin  cans,  capped, 
labeled  and  boxed.  While  not  sterile  this  product  will  keep  for 
a  long  period.  The  long  continued  heat  should  destroy  most 
bacteria  and  the  addition  of  sugar  acts  as  a  preservative. 

An  unsweetened  condensed  milk  meant  for  immediate  use  is 
put  on  the  market  by  many  condensing  companies.  The  process 
of  manufacture  is  essentially  the  same,  with  the  exception  that 
no  cane  sugar  is  added,  and  the  concentration  is  a  little  over 
three  times.  It  is  usually  sold  in  glass  jars  capped  with  paper 
caps,  similar  to  fresh  cream,  and  will  remain  sweet  and  fit  for 
consumption  as  long  as  fresh  cream. 

Evaporated  Milk. — Evaporated  milk  is  an  unsweetened  con- 
densed milk  sold  in  hermetically  sealed  cans.  As  no  cane  sugar 
is  added,  it  depends  entirely  on  sterilization  for  its  keeping 
quality.  The  raw  material  is  held  in  heating  wells  for  ten  to 
twenty  minutes,  then  is  run  directly  into  the  vacuum  pan  where 
it  is  concentrated  two  and  a  quarter  times.  After  cooling,  the 
evaporated  milk  is  immediately  put  into  cans  and  sealed.  The 
hermetically  sealed  cans  are  sterilized  at  a  temperature  of  235°  F. 
for  one-half  hour.  \Vhile  cooling,  they  are  subjected  to  shakers 
to  mix  the  jelly.  This  agitation  breaks  up  any  coagulum  which 
may  have  formed  during  sterilization.  The  cans  are  finally 
placed  in  a  curing  room  where  they  are  kept  for  thirty  days, 
after  which  they  are  examined  before  being  placed  on  the 
market.  .As  this  product  is  sterile  it  will  keep  indefinitely. 


FOOD   INDUSTRIES  227 

Concentrated  Milk. — The  Campbell  process  of  concentrating 
milk  has  placed  upon  the  market  in  recent  years  a  small  amount 
of  milk,  relatively  free  from  bacteria,  and  which  can  be  pur- 
chased at  the  price  of  ordinary  milk.  The  best  fresh  milk  which 
can  be  obtained  is  used.  After  being  tested  the  raw  product  is 
put  through  the  centrifuge,  in  order  to  clarify  it  from  stable  dirt 
and  to  separate  the  cream  and  skim  milk.  The  cream  is  pas- 
teurized, while  the  skim  milk  is  heated  for  two  or  three  hours 
at  a  temperature  of  140°  F.  during  which  a  continuous  blast  of 
filtered  air  is  driven  through  it.  Evaporation  is  continued  until 
three  parts  of  the  original  product  is  condensed  to  one  part  of 
the  concentrated  skim  milk ;  after  which  the  pasteurized  cream 
is  added.  The  product  is  placed  upon  the  market  in  small  bottles 
to  which  three  parts  of  water  must  be  added  to  give  the  original 
consistency.  On  account  of  the  low  temperature  used,  concen- 
trated milk  has  not  materially  changed  in  composition  and  after 
the  addition  of  water,  it  appears  to  have  the  properties  of  ordi- 
nary fresh  milk.  According  to  Professor  Conn,  the  method  of 
using  combined  heat  and  aeration  destroys  most  of  the  bacteria, 
especially  those  of  specific  diseases,  and  gives  a  relatively  safe 
milk  even  for  infant  feeding.  On  account  of  its  concentration 
such  milk  when  kept  below  50°  F.  will  last  for  a  week  or  ten 
days. 

Milk  Powders. — The  process  of  reducing  milk  to  the  powdered 
form  has  become  quite  an  industry  in  recent  years.  To  obtain  a 
successful  product,  the  milk  must  be  desiccated  at  a  low  tempera- 
ture in  order  to  prevent  as  little  chemical  change  as  possible  from 
taking  place.  This  is  frequently  carried  out  by  drying  it  in  a 
thin  film  on  metal  plates  in  vacuo.  The  resulting  creamy  white 
powder  \vill  unite  readily  with  water  to  give  the  original  con- 
sistency of  the  milk.  On  account  of  the  fat,  powders  prepared 
from  whole  milk  will  not  keep  indefinitely  unless  placed  in  cold 
storage;  those  from  skim  milk  have  been  found  more  satisfac- 
tory. They  are  used  to  a  large  extent  for  cooking,  especially 
where  fresh  milk  cannot  be  obtained. 


228  FOOD   INDUSTRIES 

BY-PRODUCTS  OF  THE  BUTTER  INDUSTRY. 

The  chief  industry  using  milk  is  the  butter  industry  which 
has  been  described  in  Chapter  XIII.  The  most  important  by- 
products of  this  industry  are  mentioned  below. 

Skim  Milk. — From  whole  milk  the  fat  is  separated  in  butter- 
making  very  largely  at  present  by  the  centrifuge.  With  this 
method  only  a  trace  of  the  other  constituents  is  removed  with 
the  fat;  this  leaves  the  skim  milk  rich  in  protein  and  carbo- 
hydrate. As  skim  milk  contains  all  the  normal  ingredients  of  ordi- 
nary milk  except  fat,  it  can  very  readily  be  used  for  cooking  pur- 
poses, or  as  a  beverage  for  people  who  find  cream  hard  to  digest. 
As  the  law,  however,  frequently  forbids  the  selling  of  skim 
milk,  it  has  been  utilized  to  a  great  extent  for  cattle  food  or  in 
many  cases  it  is  thrown  away.  This  is  a  waste  of  valuable 
material  for  the  protein  and  lactose  can  be  recovered  by  com- 
paratively simple  methods. 

Dried  Casein. — The  skim  milk  is  run  into  a  vat  and  a  small 
amount  of  sulphuric  or  acetic  acid  is  added.  This  precipitates 
out  the  caseinogen  in  the  form  of  a  curd  which  can  readily  be 
removed  from  the  whey,  washed,  pressed,  dried  and  sold  as 
dried  casein.  It  is  used  in  the  paper,  leather  and  textile  indus- 
tries, as  an  ingredient  of  paints,  glues,  and  cement,  and  for  the 
manufacture  of  imitation  ivory  articles. 

Milk  Sugar, — After  the  removal  of  the  caseinogen,  the  water 
may  be  evaporated  (over  hot  water)  from  the  whey  until  the 
lactose  crystallizes  out.  It  is  generally  reduced  to  the  powdered 
form  and  is  much  used  in  pharmacy  and  for  infants'  and  invalids' 
food. 

Buttermilk. — Buttermilk  is  the  fluid  which  is  left  after  churn- 
ing in  the  process  of  butter-making.  It  is  commonly  used  as  a 
food  for  young  calves  and  pigs,  and  occasionally  as  a  beverage, 
especially  during  the  summer  months.  The  chief  point  in  which 
it  differs  from  milk  is  its  poverty  in  fat  and  its  increase  in 
acidity,  due  to  the  formation  of  lactic  acid  which  rarely  exceeds 
0.5  per  cent.  It  is  comparatively  easy  to  digest  on  account  of 


FOOD   INDUSTRIES  22Q 

the  absence  of  fat  and  the  changed  condition  of  the  caseinogen, 
which  exists  in  a  finely  flocculent  form. 

Artificially  Soured  Milk. — A  milk  which  has  been  artificially, 
soured  by  the  addition  of  lactic  acid  ferments  can  now  be  found 
on  the  market,  or  can  be  prepared  at  home.  It  has  been  highly 
recommended  by  Metchnikoff.  The  product  is  prepared  by 
pasteurizing  pure  fresh  milk.  The  temperature  is  then  lowered, 
cultures  of  lactic  acid  bacteria  are  added  and  the  mass  is  held  at 
100°  F.  for  several  hours.  It  is  then  bottled  and  sold  under  a 
trade  name. 

CHEESE. 

Historical. — Cheese  has  been  known  as  a  valuable  food  for  at 
least  one  thousand  years  before  the  Christian  era.  It  is  believed 
to  be  one  of  the  oldest  products  manufactured  from  milk  and 
probably  owes  its  origin  to  the  accidental  storing  of  milk  curd. 

In  the  early  historic  days  of  the  Roman  Empire,  it  formed  an 
important  article  of  diet  and  is  still  used  as  a  chief  source  of 
protein  by  the  Italians  as  well  as  many  other  European  nations. 
It  is  largely  manufactured  at  the  present  time  in  France,  Italy, 
Germany,  England,  Switzerland  and  Holland.  The  Americans 
produce  large  quantities  of  cheese  especially  in  New  York  and 
Wisconsin,  but  do  not  as  a  nation  consume  as  much  as  the 
Europeans. 

The  industry  in  America  was  started  in  a  small  way,  prin- 
cipally by  immigrants  who  sought  to  earn  a  livelihood  in  the 
New  World  by  the  same  occupation  that  they  had  carried  on  in 
their  native  land.  This  is  particularly  true  of  the  cheese  indus- 
try in  Wisconsin,  which  owes  its  origin  to  the  settlement  of 
twenty-seven  Swiss  families  during  1845,  m  tne  rough  hilly 
country  of  Greene  County.  For  a  long  period  the  wives  and 
daughters  of  the  home  were  the  cheese  makers,  but  like  many 
other  industries,  it  was  gradually  transferred  to  the  manufac- 
turer. 

The  product  is  prepared  from  milk  by  processes  which  elim- 
inate water,  and  gather  a  large  part  of  the  solids  together,  in 
such  a  form  that  the  nourishment  is  retained  and  capable  of 


230  FOOD   INDUSTRIES 

being  preserved  for  varying  periods  of  time.  Many  varieties  are 
made  at  the  present  time.  Cow's  milk  supplies  most  of  the  raw 
material,  although  the  milk  of  the  ewe  and  goat  are  used  largely 
abroad  for  the  manufacture  of  certain  well  known  cheeses.  As 
a  rule,  milk  is  used  in  its  natural  condition  and  the  product  is 
then  known  as  whole-milk  or  full  cream  cheese.  Cream  cheese 
is  made  from  milk  and  cream,  while  skim-milk  cheeses  are  manu- 
factured from  milk  from  which  part  of  the  fat  has  been  re- 
moved. 

Whatever  the  kind  of  milk  used,  the  general  process  of  manu- 
facture is  the  same.  The  raw  material  must  be  treated  in  such 
a  way  as  to  precipitate  the  caseinogen  in  the  form  of  a  curd. 
This  may  be  accomplished  in  two  ways;  by  the  natural  develop- 
ment of  lactic  acid  and  by  the  addition  of  rennet.  The  first 
variety  known  by  some  such  name  as  pot  cheese  or  cottage 
cheese  is  not  a  true  cheese,  as  it  has  been  prepared  without  the 
use  of  rennet,  which  is  essential  in  cheese-making.  This  type 
cheese  is  prepared  more  frequently  in  the  home,  is  soft  in  texture 
and  has  poor  keeping  quality.  The  second  variety  represents 
the  many  kinds  of  domestic  and  foreign  cheese  found  in  the  mar- 
ket. 

Composition  of  Cheese. — Generally  speaking,  the  composition  of 
cheese  is  about  from  one-third  to  one-quarter  each  of  water,  fat 
and  protein,  with  a  small  amount  of  mineral  matter.  The  protein 
is  largely  predigested  having  been  changed  to  casein  by  the  action 
of  rennet.  Only  a  small  amount  of  unchanged  caseinogen  can 
be  found  while  in  many  well  cured  varieties,  through  the  action 
of  micro-organisms,  part  of  the  casein  has  been  further  changed 
to  meta-protein,  peptone  and  amino-acids.  The  mineral  matter 
consists  of  the  salts  of  milk  with  a  small  addition  of  common 
salt  to  improve  the  flavor. 

Cheese -making. — The  large  cheeses  found  in  the  American  mar- 
ket are  prepared  by  processes  more  or  less  copied  from  the  Eng- 
lish Cheddar  Process.  Cheddar  cheese  was  first  made  in  the 
village  of  Cheddar,  England,  about  250  years  ago.  It  has  grad- 


FOOD   INDUSTRIES  23! 

ually  grown  in  popularity  until  the  manufacture  has  now  spread 
over  the  civilized  world. 

PROCESS  USED  IN  CHEDDAR  CHEESE. 

I.  Straining  milk.  ] 

II.  Ripening— (82° -86°  F.). 

III.  Mixing  rennet. 

IV.  Clotting. 

V.  Cutting.  }•  Lactic  acid  fermentation. 

VI.  Stirring. 
VII.  Cooking  98°  F. 
VIII.  Removing  part  of  whey. 
IX.  Cheddaring  or  matting.        j 

X.  Grinding. 
XL  Salting. 
XII.  Pressing. 
XIII.  Curing. 

The  preliminary  treatment  of  milk  is  of  the  greatest  impor- 
tance. Successful  cheese-making  depends  to  a  great  extent  on 
the  purity  of  the  raw  material.  Great  losses  are  frequently 
caused  by  carelessness  in  the  production  and  handling  of  the 
milk  supply,  for  the  quality  of  the  milk  in  respect  to  its  cleanli- 
ness, determines  largely  the  quality  of  the  product  that  can  be 
manufactured  from  it.  The  same  cleanliness  should  be  observed 
as  in  the  production  of  market  milk,  clean  and  healthy  cows  and 
milkers,  sanitary  conditions  of  stable,  utensils  and  other  appara- 
tus. Special  attention  should  be  given  that  no  odors  can  be 
absorbed  from  manure,  pig  pens  or  silos  and  that  the  cow  has 
not  eaten  strong  smelling  food,  such  as  onions,  garlic  and  the  like. 
As  quickly  as  possible  after  being  drawn  from  the  cow,  milk 
should  be  strained  and  cooled.  To  assist  the  escape  of  volatile 
matter,  it  is  sometimes  aerated  by  being  poured  through  the  air 
from  one  container  to  another.  Stirring  also  helps  the  escape  of 
animal  odors  as  well  as  prevents  the  cream  from  rising  to  the 
top.  As  lactic  acid  is  desired,  milk  is  allowed  to  ripen  naturally 
or  by  the  addition  of  a  starter,  at  a  temperature  of  82° -86°  F. 
Tests  are  made  from  time  to  time  until  the  desired  acidity  has 
16 


232  FOOD   INDUSTRIES 

been  developed.  The  milk  is  then  run  into  shallow  rectangular 
tanks,  so  arranged  that  they  can  be  readily  tilted,  and  containing 
pipes  through  which  hot  water  can  be  circulated.  A  tempera- 
ture of  about  85°  F.  is  maintained.  While  heating  the  milk  is 
constantly  stirred  with  paddles  to  prevent  the  cream  from  rising 
to  the  top.  If  any  coloring  matter  is  to  be  added  it  is  put  in  at 
this  time.  When  thoroughly  mixed  and  of  the  desired  tempera- 
ture, the  coagulative  agent  rennet,  is  added  and  the  mass  is 
again  stirred  for  a  few  minutes  and  is  then  allowed  to  rest. 

The  active  principle  of  rennet  is  found  in  the  lining  of  the 
stomach  of  milk  fed  animals.  As  a  rule  it  is  obtained  from 
calves  although  it  has  been  taken  from  pigs  and  puppies.  Through 
the  action  of  rennet,  the  conjugated  protein  caseinogen  is  split 
into  simple  proteins,  casein  and  pseudo  nuclein,  thus  making 
cheese  a  predigested  food.  The  activity  of  rennet  is  greatly 
assisted  by  keeping  the  mass  at  body  temperature,  and  by  the 
successful  ripening  of  the  milk  in  an  earlier  stage.  The  clot  or 
curd  as  it  is  known  to  the  manufacturer,  forms  in  about  ten  to 
fifteen  minutes,  but  is  usually  allowed  to  stand  one-half  hour 
before  it  is  put  through  the  process  of  cutting.  It  is  then  firm 
enough  to  break  with  a  clean  fracture,  when  gently  pressed  with 
the  finger. 

Until  recent  years,  the  curd  was  simply  broken  into  irregular 
pieces  with  the  hand  or  some  instrument,  in  order  to  allow  the 
escape  of  the  whey.  Experimentation  has  proved  that  there  is 
less  loss  in  the  fat  content,  if  the  curd  is  cut  into  uniform  pieces. 
The  process  is  now  carried  on  by  curd  knives  which  cuts  the 
mass  into  small  cubes.  As  the  whey  makes  its  escape,  the  cubes 
sink  to  the  bottom  of  the  vat  and  are  kept  from  uniting  by  a 
gentle  agitation  of  the  entire  mass. 

In  order  to  facilitate  the  further  separation  of  the  whey,  the 
temperature  is  raised  to  98°-ioo°  F.  This  shrinks  the  curd  until 
it  is  about  one-half  of  its  former  size  and  causes  the  development 
of  more  lactic  acid.  When  sufficient  acid  has  developed,  the  whey 
is  again  removed  and  the  curd  is  allowed  to  mat  together,  various 
changes  taking  place  during  the  process.  The  curd  is  then 


FOOD   INDUSTRIES  233 

ground,  in  order  to  reduce  it  to  particles  of  convenient  size  for 
receiving  the  salt  and  pressing  it  into  shape. 

The  salt  is  added  principally  to  give  flavor.  It  has,  however, 
another  influence,  for  salt  having  a  great  attraction  for  water, 
the  curd  is  hardened.  The  mass  is  next  put  into  a  press  for 
twenty-four  hours  to  give  it  shape.  After  being  taken  from  the 
press  it  is  put  into  the  curing  room,  where  it  undergoes  fermen- 
tation for  four  or  six  weeks  or  longer.  During  this  time  the 
cheeses  are  turned  at  frequent  intervals  and  are  rubbed  on  the 
outside  with  whey  butter,  a  fatty  liquid  which  rises  to  the  top 
of  the  quietly  standing  whey. 

Curing. — As  cheese  is  not  eaten  for  its  nutritive  value  alone, 
but  more  frequently  for  the  strong  appetizing  taste,  this  part  of 
the  process  is  most  important.  It  consists  in  subjecting  the 
cheese  to  the  action  of  micro-organisms,  which  in  their  desire  for 
food,  decompose  material  giving  rise  to  characteristic  flavors. 
During  this  series  of  fermentations  which  are  not  altogether 
understood,  gases  develop  which  cause  holes  to  be  formed  in 
the  cheese.  The  ripening  process  is  carefully  guarded  as  to 
temperature  so  it  will  not  proceed  too  rapidly  or  too  far,  in 
which  case  putrefactive  fermentation  is  apt  to  set  in. 

As  much  of  the  success  of  cheese-making  depends  on  the 
curing,  bacteria  and  molds  are  now  being  carefully  studied  in 
connection  with  this  industry.  Methods  once  established  by 
which  ripening  can  be  controlled,  will  insure  a  uniform  product, 
an  extension  of  the  manufacture  of  certain  varieties  of  cheese, 
and  a  saving  of  much  money  to  the  industry. 

For  information  in  regard  to  the  manufacture  of  well  known 
cheeses,  such  as  Roquefort,  Edam,  Camembert  and  Brei,  see  a 
standard  book  on  dairy  products  as  Milk  and  Its  Products  by 
Wing  or  The  Practice  and  Art  of  Cheese-making  by  Van  Slyke 
and  Publow. 

Uncured  Cheeses. — Several  varieties  of  soft  uncured  cheeses 
may  be  found  on  the  market,  of  which  Neufchatel  and  Philadel- 
phia cream  cheese  are  the  best  known.  They  are  prepared  by 
coagulating  ripened  milk  with  rennet,  allowing  the  curd  to 


234  FOOD   INDUSTRIES 

develop  a  mild  acidity,  after  which  the  surplus  moisture  is  re- 
moved by  drainage  and  pressure.  The  curd  is  then  ground, 
salted,  molded  into  shape  and  wrapped  in  thin  paper  and  tinfoil. 

Adulteration. — The  only  extensive  form  of  adulteration  prac- 
ticed is  the  substitution  of  lard  for  the  usual  amount  of  fat. 
Lard  and  skim  milk  can  be  mixed  together  with  coloring  matter, 
put  through  a  process  first  to  emulsify  the  lard,  after  which  reg- 
ular processes  of  cheese-making  can  be  carried  out. 

Although  adulteration  has  not  been  practiced  to  any  large 
extent,  much  misbranding  of  cheese  has  been  discovered  in  the 
United  States.  Cheese  manufactured  in  this  country  has  been 
frequently  found  to  bear  a  label  conveying  the  impression  that 
the  article  is  of  foreign  make,  also,  that  the  cheese  has  been  made 
of  cream  and  milk,  when  only  whole  milk  has  been  used. 


CHAPTER  XVIII. 


PRESERVATION  OF  FOODS. 

Methods  used  in  preserving  food  material  may  be  classified 
as  follows : 

C  Drying. 
Physical    -j  Cooling. 

(  Sterilization  and  exclusion  of  air. 

f  Sugaring. 
!   Salting. 
Chemical  <(   Smoking. 

|   Use  of  fats  and  oils. 
[     "     "  spices. 

(  Borax  and  boracic  acid. 
|   Sulphurous  acid  and  salt. 
Use  of  Preservatives  <(   Benzoic 

|    Salicylic  "      "       " 

(^  Formaldehyde. 

The  attempt  to  preserve  food  material  has  been  practiced  from 
the  earliest  ages,  many  centuries  before  the  cause  of  decay  was 
understood.  This  custom  undoubtedly  arose  from  the  desire  to 
hold  provisions  obtained  in  a  successful  chase  or  during  an  abun- 
dant harvest,  for  periods  of  famine,  pestilence  and  inclement 
weather.  Modern  life  is  making  this  subject  of  vast  importance, 
for  the  crowding  of  people  into  large  cities  necessarily  means  the 
carrying  of  food  for  long  distances,  and  present  habits  of  living 
demand  the  open  market  for  twelve  months  in  the  year.  To 
meet  this  problem,  bacteriology  has  been  called  upon  to  make, 
plain  the  habits  of  the  micro-organisms,  which  live  on  food  and 
are  the  cause  of  the  decay. 

DRYING. 

Drying  is  the  oldest  and  simplest  method,  the  principle  being 
exclusively  the  withdrawal  of  water.  Mold  can  live  on  a  very 
small  amount  of  moisture  for  it  is  frequently  seen  growing  on 
damp  floors,  walls,  cloths,  food  and  the  like.  Bacteria  demand 
considerable  water  and  will  not  grow  unless  well  supplied.  They 
need  a  medium  that  is  practically  liquid,  for  they  are  only  able  to 


236  FOOD'  INDUSTRIES 

absorb  food  in  a  fluid  condition.  Many  types  of  bacteria  will 
cease  to  grow  when  the  amount  of  water  falls  to  30  per  cent, 
and  all  stop  developing  when  it  is  below  25  per  cent. 

Nature  uses  this  method  of  preservation,  for  when  the  grain 
is  ripening  much  of  the  moisture  which  was  present  in  the  green 
stage  gradually  disappears,  leaving  the  mature  grain  shriveled 
and  dry.  If  this  were  not  so,  putrefaction  would  soon  take  place. 
Much  of  our  food  material  classed  as  non-perishable,  such  as 
cereals,  starch,  sugar,  flour  and  meal  is  preserved  in  this  way. 
That  they  are  good  food  for  micro-organisms  can  readily  be 
seen  by  their  rapid  decomposition  when  water  is  added. 

Drying  seems  to  be  very  much  better  adapted  to  fruit  and 
vegetables  than  it  does  to  protein  matter,  although  meat  is  fre- 
quently shredded  and  dried  by  exposure  to  sunlight,  in  many 
parts  of  the  world  and  to  some  extent  in  the  arid  regions  of  this 
country.  It  should  only  be  practiced  in  climates  where  there  is 
little  moisture  in  the  atmosphere,  or  the  meat  will  spoil  before 
it  becomes  sufficiently  dry,  and  in  districts  far  removed  from 
crowded  habitation  where  bacterial  life  is  not  abundant.  While 
dried  meat  has  a  fair  amount  of  palatability  and  has  maintained 
all  of  the  nutritive  properties,  it  is  not  as  digestible  and  looks 
less  attractive  so  will  never  be  popular.  Dried,  smoked  or 
chipped  beef  are  common  articles  of  commerce,  but  either  smok- 
ing or  the  use  of  condiments  has  been  added  to  the  drying 
method.  This  method  is  also  used  with  the  addition  of  salt  to 
produce  a  form  of  protein  known  as  pemmican  used  extensively 
by  Arctic  explorers. 

With  fruit  and  vegetables  drying  is  very  effective.  The  sim- 
ple method  of  exposing  fruit  to  the  sunlight  was  practiced  uni- 
versally until  modern  times.  In  California  and  such  sections  as 
are  free  from  rain  and  excessive  moisture,  open-air  drying  is 
still  extensively  employed.  The  fruit  is  cleaned,  cut,  placed  on 
wooden  trays,  sterilized  with  sulphur  and  placed  in  the  sunlight 
for  five  or  six  days  or  until  sufficiently  dried.  In  other  parts  of 
the  United  States,  indoor  drying  is  now  used,  principally  on 
account  of  the  moisture  present  in  the  atmosphere. 


FOOD   INDUSTRIES  237 

Several  methods  are  used  at  the  present  time: 

I.  Fruit   is   put    in   large    drying   chambers    and    currents    of 
warm  air  are  passed  over  it.     The  water  is  withdrawn  until  25 
to  30  per  cent,  only  is  left. 

II.  Evaporation  by  vacuum  dryers  is  more  rapid  but  the  color 
is  changed.     This  may  be   overcome  by  the  use   of   chemical 
means  such  as  the  use  of  H,SO3,  called  sulphuring. 

III.  Hydraulic  pressure  has  been  found  to  be  very  effective, 
but  is  little  used. 

Many  methods  of  drying  are  trade  secrets. 

These  modern  methods  have  greatly  increased  the  number  of 
dried  products  on  the  market.  One  can  now  find  in  commerce 
peas,  beans,  apricots,  apples,  plums,  raisins,  figs,  berries  of  all 
kinds,  compressed  vegetables,  soups  with  or  without  meat,  and  a 
vast  number  of  similar  products.  Present  methods  are  also  far 
more  sanitary..  The  old-fashioned  habit  of  sun-drying  often 
meant  an  exposure  to  flies  and  dirt  of  all  kind.  The  flavor  of 
dried  fruit  is  to  some  extent  altered,  due  to  oxidation,  but  the 
nutritive  value  is  the  same  as  in  fresh  fruit. 

COOLING. 

The  principle  with  this  method  of  preservation  is  surrounding 
food  with  conditions  unfavorable  for  bacterial  development.  The 
thermal  death  point  of  micro-organisms  ranges  between  wider 
limits  than  any  other  form  of  life.  Boiling  does  not  kill  all, 
neither  does  freezing.  The  best  temperatures  at  which  to  hold 
food  in  cold  storage,  or  to  which  it  should  be  raised  with  sterili- 
zation, are  now  being  carefully  studied. 

Advantages  of  Cold  Storage. — I.  No  nourishment  is  taken 
from  food. 

II.  No  foreign  matter  is  added. 

III.  No  new  taste  is  imparted  so  the   flavor  is  not  greatly 
changed. 

IV.  The  digestibility  is  not  diminished. 

V.  A  large  quantity  of  perishable  goods  can  now  be  kept  that 
were  formally  thrown  away. 


238  FOOD    INDUSTRIES 

Disadvantages  of  Cold  Storage. — 1.  The  keeping  quality  is  im- 
paired especially  when  too  low  a  temperature  has  been  used. 
The  physical  condition  is  frequently  altered  so  bacteria  can  more 
readily  act  upon  it  as  with  meat  or  fish.  Such  food  should  be 
consumed  as  quickly  as  possible  when  taken  from  refrigeration. 

II.  Fruit  deteriorates  rapidly  after  having  been  in  cold  stor- 
age.    This  is  frequently  caused  by  a  large  amount  of  moisture 
condensing  on  the  surface  of  cold  fruit  when  taken  into  a  warm 
place,    thus    making   the    conditions    most    favorable    for    mold 
growth. 

III.  It  has  led  unscrupulous  dealers  to  hold  back  products  for 
high  prices. 

In  spite  of  these  disadvantages,  cold  storage  has  been  one  of 
the  best  methods  so  far  used  for  preserving  foods.  Beginning 
in  1860,  its  use  has  spread  enormously  and  has  made  possible 
the  uniform  distribution  of  fresh  foods,  such  as  meat,  poultry, 
eggs,  milk,  fruit,  vegetables  and  the  like  throughout  every  part 
of  the  country.  By  an  interchange  of  the  surplus  with  foreign 
nations,  it  has  vastly  improved  the  world's  food  supply  and  has 
greatly  remedied  the  enormous  waste,  in  many  sections  of  both 
hemispheres. 

Manufacturers'  methods  of  coolings  are  either  employment  of 
ice  or  the  expansion  of  compressed  gas,  as  used  in  the  ammonia 
process.  The  housewife  must  as  a  rule  depend  upon  an  ice 
chest  which  is  generally  kept  too  warm.  The  temperature  of  an 
ordinary  refrigerator  registers  from  50°  to  60°  F.,  whereas  it 
should  be  kept  below  50°  F. 

Precautions  in  Care  of  Chest. — I.  Do  not  wrap  ice  in  news- 
paper. It  is  only  in  melting  that  low  temperature  is  maintained. 

II.  Keep  ice  chest  well  filled  with  ice. 

III.  Keep  the  chest  as  dry  as  possible  as  cold  damp  air  harbors 
many  low  forms  of  plant  and  animal  life. 

IV.  Charcoal  should  not  be  utilized  for  lining  as  it  soon  be- 
comes clogged  and  makes  a  fine  incubator  for  bacteria. 

V.  Wash   frequently  with   warm   water  and   a   neutral   soap. 


FOOD   INDUSTRIES  239 

STERILIZATION  AND  EXCLUSION  OF  AIR. 
See  Chapter  XIX.     The  Canning  Industry. 

SUGARING. 

Preserving  by  means  of  sugar  is  not  used  to  as  large  an  extent 
to-day  as  it  was  in  former  years.  The  great  improvements 
achieved  by  canning  manufacturers  have  made  their  products  so 
popular  that  they  have  largely  taken  the  place  of  the  old-fashioned 
preserves. 

The  principle  of  the  sugaring  method  is  surrounding  food  with 
conditions  unfavorable  for  growth  of  micro-organisms.  Bac- 
teria do  not  grow  well  in  a  pure  sugar  solution  unless  it  is  very 
weak.  If  the  solution  be  strong,  development  is  entirely  pro- 
hibited. Yeasts  will  sometimes  grow  and  cause  fermentation  to 
set  in,  but  this  cannot  take  place  if  the  sugar  is  as  high  as  40-50 
per  cent.  The  old-fashioned  housekeeper's  recipe  usually  read — 
"A  pound  of  sugar  to  a  pound  of  fruit,"  thus  the  product  was  as  a 
rule  protected  against  fermentation.  It  was  quite  possible,  how- 
ever, for  mold  to  grow,  but  the  formation  always  occurred  on 
the  surface  and  could  readily  be  removed. 

The  great  disadvantage  with  this  method  is  the  altered  taste. 
Sugar  is  added  in  such  large  quantities  that  the  strength  of  its 
flavor  conceals  or  destroys  other  flavors  that  are  desired,  as  the 
pleasant  acidity  of  many  fruits.  A  second  inconvenience  is  the 
large  quantity  of  sugar  that  is  required  in  order  to  preserve  a 
small  quantity  of  fruit,  hence  the  use  of  it  is  very  expensive. 
Preserved  fruits  are  used  to-day,  only  as  a  sweetmeat. 

It  has  been  found  possible  to  preserve  meat  and  fish  by  the 
use  of  sugar  alone.  Although  this  method  has  never  been  used 
with  protein  material  in  America,  it  is  still  customary  in  Por- 
tugal to  preserve  fish,  as  the  salmon,  by  splitting,  cleaning  and 
sprinkling  the  interior  with  sugar.  It  is  said  that  fish  prepared 
in  this  way  can  be  kept  for  a  long  time  with  a  perfectly  fresh 
flavor. 

SALTING. 

The  keeping  of  food  material  with  salt  has  been  used  from 
very  early  times.  The  discovery  of  its  preservative  action  was 


240  FOOD   INDUSTRIES 

probably  accidental,  due  to  the  finding  of  animal  carcasses  em- 
bedded in  the  saline  deserts  of  Asia.  Ancient  wine  makers  fre- 
quently used  salt  water  with  the  object  of  keeping  their  product 
for  a  longer  period,  and  Pliny  speaks  of  flesh  food  being  treated 
with  salt  and  meat  being  preserved  with  brine.  The  custom  of 
salting  fish  was  also  known  to  the  Greeks  and  Romans,  but  it 
seemed  to  have  been  used  more  as  an  incentive  to  the  consump- 
tion of  wine  than  because  of  any  wish  to  add  to  the  keeping 
quality  of  the  product. 

The  principle  of  its  protective  power  lies  largely  in  the  with- 
drawal of  moisture,  for  salt  has  a  great  attraction  for  water. 
Bacteria  cannot  develop  in  food  impregnated  with  salt  so  it  can 
be  preserved  indefinitely  by  this  method. 

A  variety  of  foods  can  be  salted  as  olives,  nuts  and  pickles,  but 
this  process  has  been  used  to  the  greatest  extent  with  meats  and 
fish. 

Different  methods  may  be  used : 

I.  Rubbing  dry  salt  into  meat. 

II.  Pickling  or  the  use  of  a  saturated  salt  solution. 

III.  Salting  and  the  addition  of  smoking  or  drying. 
Advantage. — I.  Salt  is  harmless  and  is  needed  in  the  diet. 
Disadvantages. — I.  The  flavor  is  greatly  changed. 

II.  The  physical  nature  of  meat  or  fish  is  changed,  fiber  is 
toughened  so  the  product  is  not  as  digestive. 

III.  Nourishment   is   lost  as  certain   constituents   of   protein 
matter  are  soluble  in  a  salt  solution  and  are  lost  in  the  brine.    A 
saturated  salt  solution  also  renders  protein  more  or  less  insol- 
uble, hence  it  is  not  all  available  as  food. 

On  the  whole,  salting  has  not  been  found  satisfactory.  The 
destruction  of  taste  and  the  reduced  nutritive  value  are  serious, 
and  other  methods  of  preservation  have  to  a  great  extent  taken 
its  place. 

SMOKING. 

The  art  of  smoking  meat  and  fish  to  assist  in  its  preservation 
has  been  practiced  from  remote  ages.  The  custom  probably 
originated  from  the  habit  of  suspending  such  food  material 


FOOD   INDUSTRIES 


241 


within  the  tent  or  primitive  dwelling.  Being  close  to  an  open 
wood  fire,  smoke  arose  saturating  the  hanging  material  and  not 
only  gave  it  an  agreeable  taste,  but  greatly  assisted  in  the  keeping 
quality.  This  simple  practice  is  still  largely  followed  in  isolated 
sections.  Small  smoke-houses  are  frequently  found  in  many 
parts  of  the  country,  where  meat  or  fish  can  be  laid  across  slats 
near  the  roof  and  smoke  from  a  wood  fire  allowed  to  pass  over  it. 


Fig.  61. — The  Sausage  Smoke  House.     (Courtesy  of  Armour  &  Co.,  Chicago,  111.) 

The  preservative  action  is  now  known  to  be  due  to  certain 
products  present  in  the  smoke,  such  as  creosote,  which  contains 
a  bactericidal  substance  known  as  guaiacol.  Formaldehyde  and 
acetic  acid  are  also  present  in  smoke,  but  as  they  are  extremely 
volatile,  they  are  of  little  use.  Creosote  being  less  volatile 
remains  on  the  exterior  of  the  meat  and  acts  as  a  violent  germi- 
cide, while  being  perfectly  harmless  to  the  human  consumer  of 
the  product.  Since  many  woods  also  yield  turpentine  on  burn- 
ing, it  is  necessary  to  select  beech,  hickory,  oak  or  such  woods 
as  yield  creosote  and  not  organic  compounds  which  would  affect 


242  FOOD   INDUSTRIES 

the  flavor.     Water  plays  an  important  part  in  the  production 
of   creosote  so  generally  the  wood  is  used  in  the  green  state 


Smoking  does  not  protect  against  all  forms  of  micro-organ- 
isms. Mold  can  attack  food  preserved  in  this  way,  but  it  is 
usually  only  on  the  surface  and  can  readily  be  removed  with  a 
cloth  dampened  with  lard  or  sweet  oil.  Canvas-covered  meats 
are  less  likely  to  be  attacked  by  mold.  As  smoking  does  not 
reach  the  interior,  only  material  free  from  contamination  should 
be  used. 

It  is  quite  customary  to  combine  salting  and  sugaring  with 
smoking  as  in  sugar  cured  hams.  If  such  products  are  of  a 
high  grade,  they  are  immersed  in  a  pickle  compound  of  salt, 
salt-petre,  sugar  and  spices  for  forty  to  sixty  days,  after  which 
they  are  placed  in  a  smoke-house  for  three  days.  This  process 
is  excellent  but  it  is  long  and  increases  the  cost,  so  a  quicker, 
cheaper  method  is  occasionally  substituted.  Brine  is  pumped 
into  the  ham  and  the  product  is  then  treated  with  smokine.  This 
preservative  contains  minute  particles  of  creosote  in  solution 
and  may  be  applied  by  a  brush  or  by  dipping  meat  quickly  into 
the  solution  and  afterwards  drying  it.  This  method  is  not  as 
effective  as  the  use  of  the  old-fashioned  smoke-house  and  the 
cresote  is  more  likely  to  penetrate. 

USE  OF  FATS  AND  OILS. 

Foods  which  do  not  contain  a  large  amount  of  fat  are  very 
good  put  up  in  oil,  sterilized  and  sealed  to  prevent  the  oil  from 
becoming  rancid.  A  coating  of  oil  is  also  frequently  used  to 
preserve  foods  by  the  exclusion  of  air.  This  method  has  been 
used  largely  abroad  where  birds  are  dried  and  saturated  with 
oil;  goose-livers  similarly  treated  are  sold  as  "pate-de-foie- 
gras."  These  products  are  considered  great  delicacies.  In  Italy 
wine  is  often  covered  with  oil  to  prevent  bacterial  action,  and  in 
Arctic  regions  many  kinds  of  meat  are  frequently  preserved  in 
this  way.  Possibly  the  most  common  food  on  our  market  put 
up  in  oil  is  the  sardine  although  tuna  fish,  salmon,  mushrooms, 
truffles  and  artichokes  are  also  important  products. 


FOOD   INDUSTRIES  243 

The  name  sardine  was  originally  given  to  a  variety  of  fish 
found  in  the  Mediterranean  near  the  Island  of  Sardinia  but  the 
commercial  usage  now  includes  several  varieties,  the  French 
sardine  being  the  young  of  the  pilchard,  and  the  American, 
young  herring. 

During  the  process  of  manufacture  the  fish  are  carefully 
sorted  into  sizes,  cleaned,  placed  in  brine,  washed  in  fresh  water, 
dried  in  the  open  on  trays,  immersed  in  oil,  boxed  and  sterilized. 
Olive  and  peanut  oils  are  largely  used  abroad  while  cottonseed 
is  frequently  substituted,  especially  in  America.  As  a  rule  the 
French  sardine  receives  greater  care  in  the  manufacture  and  is 
supposed  to  improve  with  age  caused  by  the  blending  of  fish,  oil 
and  flavoring. 

This  method  of  preservation  is  also  used  in  Germany  in  the 
manufacture  of  sausages.  In  the  German  market,  two  types  of 
sausage  can  be  found:  those  so  rich  in  fat  that  they  can  be  kept 
for  some  time;  and  those  which  are  lean  and  must  depend  upon 
the  preservative  influence  of  the  high  content  of  spices.  The 
casing  in  both  types  is  more  or  less  impervious  to  any  material. 

USE  OF  SPICES 

Spices  were  originally  added  to  food  to  change  or  modify  the 
flavor,  but  it  has  been  found  that  they  exercise  a  powerful  pre- 
servative effect.  See  Chapter  XXII.  Spices. 

ALCOHOL. 

Alcohol  makes  all  protein  matter  insoluble  thus  killing  all 
bacterial  life.  For  this  reason,  it  is  used  largely  in  preserving 
biological  specimens.  To  a  slight  extent  it  is  also  used  for  foods. 
Fruit  of  all  seasons  can  be  put  down  in  an  alcohol  solution  and 
preserved  indefinitely. 

USE  OF  PRESERVATIVES. 

It  is  well  known  that  certain  chemicals  when  added  to  food 
have  a  restraining  influence  upon  bacteria,  yeast  and  molds 
which  are  associated  with  its  decomposition.  Some  simply  pre- 
vent the  further  development,  others  act  as  strong  bactericidal 
agents.  In  the  early  days  of  the  canning  industry,  they  were 


244  FOOD   INDUSTRIES 

largely  used  but  modern  methods  of  sanitation  and  sterilization 
by  heat  have  proved  so  much  more  reliable  and  less  expensive, 
that  manufacturers  of  legitimate  products  have  now  almost  en- 
tirely abandoned  their  use,  regardless  of  the  Pure  Food  Law. 

The  harmful  nature  of  these  chemical  compounds  has  been  ar- 
gued for  and  against  for  a  long  period.  At  the  present  time  prob- 
ably all  agree  that  their  use  is  absolutely  unnecessary  for  goods 
that  are  to  be  consumed  within  a  short  period.  There  is  still, 
however,  much  discussion  as  to  their  use  in  such  products  as 
chili-sauce,  ketchup,  apple  butter  and  other  foods  classed  as  rel- 
ishes. These  products  have  been  cooked  thus  making  them  more 
susceptible  to  bacterial  action  after  being  opened.  As  they  are 
usually  held  for  a  length  of  time,  too  frequently  under  careless 
conditions,  they  are  apt  to  become  undesirable  articles  of  food. 
For  this  reason,  benzoate  of  soda  or  other  preservative  is  fre- 
quently added  in  small  amounts. 

Arguments  advanced  in  favor  of  their  use  are: 

I.  These  antiseptics  are  harmless  when  used  in  small  amounts. 
One  part  salicylic  acid  in   1,000  is  not  injurious  and  may  be 
beneficial  in  warding  off  intestinal  diseases. 

II.  They  are  found  occurring  naturally  in  many  of  our  fruits 
such  as  currants,  cranberries,  raspberries  and  crab-apples. 

III.  These  antiseptics  are  frequently  developed  during  manu- 
facturing processes  especially  where  sterilization  by  high  tem- 
peratures is  necessary. 

Arguments  against  their   use: 

I.  They  are  not  violent  poisons,  but  are  believed  to  be  unde- 
sirable as  they  are  antifermentatives  so  interfere  with  the  diges- 
tive  ferments. 

II.  They  are  irritants  so  are  apt  to  injure  the  mucous  mem- 
brane of  the  stomach  and  intestinal  canal. 

III.  The  blood  has  for  its  chief   function  oxidation.     These 
chemical  compounds  interfere  with  the  blood  doing  its  work  of 
oxidation. 


FOOD   INDUSTRIES  245 

IV".  The  amount  is  not  always  small. 

Possibly  the  strongest  reasons  for  prohibiting  their  use  are 
that  it  may  lead  to  carelessness  in  manufacturing  processes  and 
to  the  use  of  inferior  material.  Neither  can  they  be  regarded  as 
"cure-alls"  for  they  do  not  affect  ptomaines  which  cause  disease. 

Artificial  Sweetening. — Saccharine  has  been  largely  used  for 
sweetening  syrups,  preserves,  jams,  jellies,  canned  goods  and 
similar  products.  It  is  a  glistening  white  powder  resembling 
sugar,  but  with  a  much  greater  sweetening  power,  thus  making 
it  a  cheaper  agent  to  use.  Saccharine  is  obtained  by  the  oxida- 
tion of  one  of  the  coal  tar  products  and  has  no  food  value.  It 
is  believed  to  be  an  irritant  so  its  use  has  been  forbidden. 

Artificial  Coloring. — The  employment  of  artificial  coloring  in 
connection  with  food  has  been  practiced  for  the  past  fifty  years. 
The  colors  have  included  animal,  vegetable  and  mineral  dyes  for  a 
long  period  and  recent  years  have  added  an  innumerable  -number 
of  coal  tar  dyes  to  the  list.  The  animal  and  vegetable  dyes  have 
included  cochineal,  annatto,  turmeric,  logwood,  saffron  and  carrot 
juice,  which  are  generally  supposed  to  be  harmless.  At  present 
the  only  mineral  dyes  being  used  to  any  extent  are  copper  sul- 
phate in  green  vegetables  and  fruit,  oxide  of  iron  in  coco,  con- 
fectionery, condiments,  sausages  and  the  like  and  Prussian  blue 
in  sugar  refining. 

Copper  sulphate  is  generally  considered  to  have  a  deleterious 
effect  on  the  consumer  but  it  is  not  known  to  be  cumulative  as  in 
the  case  of  lead.  Its  use  is  prohibited  in  Germany,  Austria 
and  Hungary  and  is  limited  in  many  other  European  nations. 
The  United  States  does  not  forbid  its  being  added  to  food 
material  but  the  amount  must  be  stated. 

The  coal  tar  dyes  are  unlimited  in  variety  and  are  used  ex- 
tensively in  confectionery,  jellies,  jams,  meat,  dairy  products, 
wines  and  non-alcoholic  beverages.  Usually  the  amount  is  very 
small  rarely  exceeding  one  part  in  one  hundred  thousand  and 
for  this  reason,  it  is  almost  impossible  to  form  an  opinion  in 
regard  to  whether  or  not  it  is  injurious  to  health.  While  such 
coloring  matter  may  not  be  detrimental  to  the  consumer,  the  use 


246 


FOOD   INDUSTRIES 


is  unfortunate  for  it  enables  the  manufacturer  to  place  inferior 
goods  upon  the  market  for  high  grade  material.  Articles  of 
food  are  much  preferable  in  their  natural  color,  and  it  is 
unfortunate  that  the  housewife  so  frequently  prefers  highly 
colored  goods  thus  encouraging  the  use  of  artificial  coloring 
matter. 


CHAPTER  XIX. 


THE  CANNING  INDUSTRY. 

Historical. — The  process  of  food  preservation  by  canning  was 
invented  in  1810  by  Nicholas  Appert  of  Paris.  The  underlying 
principle  of  this  method,  the  destruction  of  all  life  by  means 
of  heat  followed  by  the  exclusion  of  air  by  hermetically  sealing, 
was  established  by  the  experimental  work  of  Spallanzani,  in 
1765.  By  placing  various  nutritive  liquids  in  tubes,  sealing,  and 
boiling  them  for  an  hour,  he  discovered  that  the  liquid  remained 
unchanged,  as  long  as  the  seal  was  unbroken. 

During  the  warfares  of  Napoleon,  much  dissatisfaction  occurred 
in  regard  to  the  food  that  his  army  was  obliged  to  eat  while  on 
the  march.  An  investigation  followed  which  led  to  the  offering 
of  a  prize  of  12,000  francs  to  any  man  who  could  keep  food 
indefinitely  in  its  natural  condition  without  adding  the  preserva- 
tives then  in  use,  which  included  salt,  sugar,  vinegar  and  smoke. 
It  was  won  by  Appert,  who,  after  long  practical  experience  in 
confectioneries,  kitchens,  breweries  and  distilleries,  had  been 
working  for  many  years  along  the  line  of  food  preservation,  using 
the  theory  advanced  by  Spallanzani.  Food  material  was  placed 
in  air  tight  containers  after  it  had  been  subjected  to  such  a  de- 
gree of  heat  that  the  contents  had  been  thoroughly  sterilized.  The 
apparatus  used  by  Appert  was  necessarily  very  crude  but  his 
discoveries  laid  the  foundation  for  one  of  the  greatest  industries 
of  modern  times. 

About  the  same  time,  Peter  Durand  obtained  a  patent  in  Eng- 
land for  preserving  meat,  fruit  and  vegetables  in  tin  cans,  and 
shortly  after  several  other  manufacturers  introduced  similar 
methods.  The  theory  upon  which  these  men  worked  was,  that 
the  oxygen  contained  in  air  was  the  destructive  agency  and  its 
exclusion  alone  would  preserve  food  which  had  been  cooked. 
It  was  not  until  the  time  of  Tyndall  and  Pasteur  that  the  real 
cause  of  putrefaction  was  understood.  The  industry  was  estab- 
lished in  the  United  States  by  Ezra  Daggett,  who  after  learning 
the  trade  abroad  canned  salmon,  lobsters  and  oysters  in  New 
17 


248  FOOD   INDUSTRIES 

York  in  1819.  Shortly  afterward  William  Underwood  started 
to  pack  tomatoes,  and  in  1837  Isaac  Winslow  began  experimenting 
with  the  canning  of  corn  in  Portland,  Maine.  Spreading  grad- 
ually throughout  the  east,  this  industry  was  finally  introduced  into 
the  middle  west  about  the  time  of  the  breaking  out  of  the  Civil 
War  and  within  a  year  or  two,  we  find  its  establishment  in  Cali- 
fornia. An  enormous  impetus  was  given  to  canning  when  it  was 
discovered  that  canned  goods  were  vastly  superior  to  dried  food 
in  palatability,  for  army  use.  The  growth  of  the  industry  since 
that  time  has  been  very  rapid  and  at  the  present  time,  canneries 
are  scattered  throughout  the  United  States.  Along  the  Atlantic 
Coast,  large  quantities  of  vegetables,  meat  and  fish  are  preserved. 
Oregon  and  Washington  supply  much  of  the  salmon,  Chicago 
packs  largely  meat,  while  California  furnishes  fruit  and  vege- 
tables of  the  highest  grade. 

The  rapid  growth  soon  led  to  new  and  better  methods  of  making 
cans,  great  improvements  in  machinery,  skilled  workers  and  much 
experimentation  in  regard  to  the  best  methods  of  sterilization. 
In  the  latter  work  manufacturers  have  been  greatly  assisted  by 
scientific  investigation. 

While  the  United  States  puts  out  enormous  quantities  of  certain 
products,  such  as  corn,  tomatoes  and  salmon,  European  coun- 
tries have  a  considerably  larger  variety  of  articles-.  Numerous 
combinations  of  mixed  vegetables,  meat  and  vegetables  and  meat 
delicacies  are  placed  on  the  market,  one  country  alone  having 
canneries  whose  output  includes  several  hundred  different  items. 
The  future  possibilities  of  this  industry,  both  at  home  and  abroad, 
are  very  great  if  by  rigid  inspection,  only  canned  foods  consisting 
of  good  wholesome  material,  packed  with  proper  care  under  sani- 
tary conditions  are  placed  upon  the  market. 

Process. — As  before  stated,  the  two  principal  points  to  be  borne 
in  mind  in  the  preservation  of  foods  by  canning  are: — ist,  the 
destruction  of  all  micro-organisms  and  their  spores  by  means  of 
heat ;  2nd,  the  exclusion  of  air  by  hermetically  sealing.  As  a  rule, 
the  can  and  food  are  sterilized  at  the  same  time  but  the  details  of 
the  process  necessajrily  vary  with  different  products  and  in 


FOOD   INDUSTRIES 


249 


various  canneries.  Fruit  and  vegetables  should  be  selected  when 
at  their  best,  transported  as  quickly  as  possible  to  the  factory  and 
immediately  sorted  for  quality.  They  are  then  washed,  treated 
according  to  the  product  and  placed  at  once  in  cans.  Care  is 
given  that  the  cans  are  filled  full,  then  closely  covered  with  the 
exception  of  a  small  hole  for  exit  of  steam.  They  are  then 
subjected  to  the  temperature  of  boiling  water  or  higher  according 
to  the  material.  The  hole  is  immediately  closed  with  solder,  the 


Fig.  62.— Stock  Boilers.     (Courtesy  of  the  Franco-American  Food  Co.) 


cans  reheated  and  allowed  to  cool.  Some  factories  accomplish 
the  same  result  by  means  of  a  steam  heated  "exhaust  box,"  which 
withdraws  part  of  the  air  in  the  filled  cans,  before  they  are  sent 
to  the  capping  department.  With  either  method  a  partial  vacuum 
is  formed  within  the  can  which  causes  the  end  to  be  depressed. 
Should  the  process  of  sterilization  be  imperfect  and  bacteria  or 
their  spores  be  left  within  the  can,  fermentation  soon  starts  in 
and  the  formation  of  gas  causes  the  top  to  bulge.  Canned  goods 
are  usually  kept  for  one  month  and  are  then  tested  by  striking 


250 


FOOD   INDUSTRIES 


with  the  finger.  Expert  examiners  are  able  to  tell  by  the  sound 
if  a  partial  vacuum  still  remains. 

With  the  best  manufacturers  all  cans  which  show  the  presence 
of  gas  are  thrown  away.  In  some  factories,  however,  they  are 
resterilized.  This  practice  is  dangerous,  as  injurious  products 
may  have  developed  which  are  not  affected  by  reheating  (Figs. 
62  and  63). 

Success  of  Canning. — There  has  been  a  great  difference  with 
various  foods  in  regard  to  successful  canning.  Fruits  are  more 


Fig.  63.— Sterilizing  Process.     (Courtesy  of  the  Franco- American  Food  Co.) 

subject  to  yeast  and  molds  which  are  killed  at  a  comparatively 
low  temperature,  so  have  given  little  trouble.  Tomatoes,  corn 
and  peas,  however,  have  been  successfully  canned  only  after 
much  experimentation.  Even  after  careful  treatment  and  seal- 
ing, these  products  have  frequently  undergone  the  putrefactive 
changes  that  it  was  the  purpose  of  canning  to  prevent.  Through 
scientific  investigation,  the  discovery  was  made  that  these  vege- 
tables are  invaded  with  bacteria,  the  spores  of  which  will  resist 


FOOD   INDUSTRIES  251 

heat  for  a  length  of  time.  If  when  the  can  is  sealed  a  single 
spore  remains  alive,  it  is  capable  of  completely  ruining  the  prod- 
uct in  the  course  of  time.  For  a  long  period  it  was  thought 
impossible  to  can  green  corn,  for  that  vegetable  had  given  the 
manufacturer  more  trouble  than  any  other  product.  With  the 
aid  of  the  bacteriologist,  the  problem  has  been  completely  solved. 
Corn  is  not  only  invaded  by  extremely  resistant  spore  bearing 
bacteria,  but  the  kernels  are  not  easily  penetrated  by  heat.  Those 
which  lie  next  to  the  can  are  easily  sterilized  but  the  interior 
layers  do  not  heat  readily.  For  this  reason  a  thermometer  is 
usually  put  in  the  center  of  a  test-can  and  the  temperature  is 
carefully  registered.  It  has  been  found  necessary  to  use  250°  F. 
for  65  minutes  in  order  to  kill  all  spores  present. 

Regardless  of  the  product,  the  success  of  canning  depends  on 
the  sanitary  conditions  which  preVail  throughout  the  factory,  the 
quality  of  the  material  and  the  rapidity  with  which  it  is  handled. 

Meat  Products. — In  the  canning  of  meat,  the  fore-quarter  as  a 
rule  is  used,  the  hind-quarter  selling  better  as  fresh  meat.  Al- 
though this  may  mean  a  poorer  grade  meat,  it  does  not  necessarily 
indicate  that  it  is  any  less  healthy.  Before  sterilization,  meat  is 
usually  cut  into  uniform  pieces,  as  different  sizes  would  mean 
disintegration  of  the  smaller  pieces,  before  the  larger  ones  are 
cooked,  thus  giving  a  bad  appearance  to  the  finished  product. 
The  meat  is  then  par-boiled  for  8-20  minutes  to  secure  shrinkage 
before  being  put  in  cans.  The  further  processes  of  sterilization 
and  exclusion  of  air  are  quite  similar  to  those  used  in  other 
canning  industries. 

A  large  variety  of  potted  and  deviled  meat  can  also  be  found 
on  the  market.  As  the  process  of  manufacture  is  usually  a  trade 
secret  their  exact  composition  is  difficult  to  determine,  but  they 
are  largely  composed  of  beef  or  pork,  mixed  with  spices  and 
flavoring,  the  larger  amount  of  condiments  being  used  with  the 
deviled  varieties. 

Containers. — Manufacturers  use  either  glass  or  tin  in  preserv- 
ing. The  preference  usually  is  in  favor  of  glass  but  it  is  a  ques- 


252  FOOD    INDUSTRIES 

tion  whether  this  is  warranted,  except  in  certain  products  which 
cannot  be  preserved  to  the  best  advantage  in  tin. 

Advantages  of  Glass. — I.  Food  material  such  as  fruit  or  vege- 
tables look  very  attractive. 

II.  It  contains  no  lead  or  other  dangerous  material. 

III.  In  the  household  it  is  much  easier  to  handle. 
Disadvantages  of  Glass. — I.  The   jars  to  be   strong  must  be 

made  of  thick  glass  which  is  likely  to  break  with  a  sudden  change 
of  temperature.     They  also  break  easily  if  struck  with  a  blow. 

II.  They  cannot  be  handled  with  automatic  machinery. 

III.  Transportation  is  difficult  on  account  of  the  weight  and 
liability  to  break.     They  occupy  too  much  space. 

IV.  It  is  frequently  necessary  to  cover  the  glass  with  paper 
as  light  has  a  bleaching  effect  on  some  products. 

Caution. — When  glass  jars  are  used  in  the  home  they  must 
be  made  air  tight.  This  is  a  difficult  thing  to  do  especially  where 
rubber  bands  are  used.  Old  rubber  bands  have  lost  their  elas- 
ticity so  are  not  safe  to  use.  It  pays  to  buy  new  ones.  As  sul- 
phur has  been  used  to  impart  elasticity  and  to  keep  the  rubber 
from  sticking,  the  new  bands  should  be  moistened  before  using. 

Advantages  of  Tin  Containers. — I.  They  are  light  to  -handle 
and  occupy  less  space  in  storing  and  during  transportation. 

II.  They  are  less  likely  to  break. 

III.  Products  are  protected  from  light. 

IV.  They  are  much  easier  to  make  air-tight. 

V.  Tin  cans  cannot  be  refilled. 

VI.  If  a  good  quality  of  tin  has  been  used  and  the  can  carefully 
made,  there  is  no  danger  of  poisoning. 

Disadvantages  of  Tin  Containers. — I.  Tin  cans  are  not  prac- 
tical for  use  in  the  household. 

II.  They  are  dangerous  if  a  poor  grade  of  tin  has  been  used 
or  the  process  of  manufacture  has  not  been  thoroughly  carried 
out. 

III.  With  such  products  as   raspberries,  cherries,  plums  and 
beets,  they  are  not  desirable  as  the  tin  coating  is  attacked  resulting 
in  a  loss  of  color,  flavor  and  quality.     Salts  of  tin  are  also  formed 


FOOD    INDUSTRIES 


253 


which  are  objectionable.  For  the  protection  of  such  products 
a  recent  improvement  has  been  made  by  coating  or  lacquering  the 
inside  of  the  can.  While  such  coatings  are  not  perfect,  they  are 
a  step  in  advance  and  further  improvement  will  undoubtedly  be 
made  in  the  near  future. 

According  to  work  done  by  the  United  States  Department  of 
Agriculture,*  such  products  as  corn,  peas,  beans  and  tomatoes 
have  little  action  on  tin  so  a  coating  is  unnecessary. 


Fig.  64.— Can  Closing  Machines.     (Courtesy  of  the  Franco- American  Food  Co.) 

On  the  wrhole  there  is  practically  little  risk  now  in  the  use  of 
tin,  as  the  manufacture  of  cans  has  greatly  improved.  They  are 
made  of  sheet  iron  which  has  been  cleaned  and  foiled  out  to  the 
proper  thickness,  dipped  into  acid  to  remove  oxide,  put  quickly 
into  water  then  dried,  after  which  the  sheet  is  dipped  quickly 
into  melted  tin.  Before  being  made  into  cans  by  machinery  they 
are  carefully  examined.  If  the  oxide  has  not  been  removed  the 

*  The  Canning  of  Foods.     Bulletin  No.  151.     Bureau  of  Chemistry. 


254  FOOD    INDUSTRIES 

tin  will  not  stick,  thus  leaving  the  iron  exposed  to  the  action  of 
organic  acids  occurring  in  fruits  and  vegetables.  All  imperfectly 
made  sheets  are  rejected.  The  modern  can  is  made  with  lock 
seams  and  outside  soldering  (Fig.  64).  As  the  sealing  in  many 
cases  is  done  by  double  seaming  on  the  top,  no  solder  is  used 
except  on  the  side  seam.  This  overcomes  possible  contamination 
by  solder  in  contact  with  food  material. 

To  insure  the  safe  usage  of  products  packed  in  tin,  it  is  abso- 
lutely necessary  that  the  contents  be  removed  after  the  can  has 
been  opened,  to  prevent  oxidation. 

Adulteration. — Since  modern  methods  of  sterilization  have  been 
employed,  the  use  of  preservatives  has  been  practically  abandoned 
in  the  canning  industry,  as  they  simply  add  to  the  cost.  Saccharine, 
bleaches  and  coloring  matter  now  constitute  the  chief  adulterants. 
Saccharine  is  frequently  added  to  corn,  tomatoes  and  peas  to  dis- 
guise the  fact  that  sweet  varieties  of  the  garden  vegetable  have 
not  been  used.  A  bleaching  agent  is  frequently  employed  to 
whiten  corn,  and  peas  are  given  a  bright  green  shade  by  the 
addition  of  copper  salts.  During  canning  and  on  standing  peas 
are  apt  to  lose  part  of  the  chlorophyl  through  oxidation  processes, 
which  give  them  a  yellowish  appearance.  Copper  salts  will  unite 
with  the  nitrogenous  constituents  of  the  peas  to  form  a  compound 
with  a  brilliant  green,  thus  restoring  the  original  color,  although 
the  shade  lacks  the  delicacy  of  the  natural  green.  The  coloring 
of  peas  is  largely  practiced  in  France,  but  as  a  rule  is  not  used 
by  American  canners.  Very  little  adulteration  has  been  found 
in  tomatoes  except  the  addition  of  coloring  matter  such  as  coch- 
ineal or  coal  tar  dye.  The  artificial  coloring  has  been  used  to 
make  inferior  material  appear  as  mature  and  high  grade  tomatoes. 

The  adulteration  of  canned  meat  is  probably  more  often  prac- 
tised than  with  vegetables,  but  it  has  been  found  by  no  means 
common,  by  the  Bureau  of  Chemistry.  It  consists  largely  in  the 
substitution  of  cheaper  meats  and  fat  and  the  addition  of  starch 
to  increase  bulk  and  weight.  Coloring  matter  and  preservatives 
as  borax,  boracic  acid  are  still  occasionally  found. 


CHAPTER  XX. 


TEA,  COFFEE  AND  COCO. 


TEA. 

Historical. — According  to  the  writings  of  an  ancient  Chinese 
author,  the  virtues  of  tea  were  known  in  the  Orient  some  2,700 
years  before  the  Christian  era.  Many  legends  exist  as  to  its 
original  home,  some  claiming  that  it  was  first  grown  in  China, 
while  others  speak  of  its  introduction  into  that  kingdom  from 
one  of  the  neighboring  provinces  of  India. 

For  a  long  period  it  seems  to  have  been  used  as  a  medicine 
rather  than  as  a  beverage.  Gradually  growing  in  popularity, 
however,  it  eventually  became  a  national  drink  and  the  cultiva- 
tion of  the  tea  plant  for  this  purpose  grew  to  be  an  important  in- 
dustry in  China,  Japan,  India  and  Ceylon. 

It  was  not  until  the  later  part  of  the  i6th  century  that  the 
Dutch  East  India  Co.,  in  their  journeys  to  the  Orient,  carried 
back  to  Holland  some  of  the  curiosities  of  the  Eastern  World, 
one  of  them  being  Chinese  tea.  Knowledge  of  it  finally  went  to 
England  and  in  1657,  we  hear  of  the  first  tea-house  being 
opened  in  Exchange  Alley,  London.  For  many  years  the 
price  per  pound  was  so  high  that  tea  was  looked  upon  as  a  rare 
luxury,  but  by  the  latter  part  of  the  I7th  century  it  was  being 
imported  from  China  in  such  large  amounts,  that  it  ceased  to  be 
a  rarity.  As  the  price  lowered  the  annual  consumption  grew 
until  at  the  present  time  Great  Britain  uses  considerably  more 
than  one-half  of  the  world's  total  production.  Tea  was  intro- 
duced into  the  colonies  as  early  as  1680,  the  price  at  that  time 
being  five  or  six  dollars  per  pound,  for  the  cheapest  varieties. 

Cultivation  of  the  Tea  Plant. — The  tea  plant  is  a  hardy  ever- 
green shrub,  which  grows  to  a  height  of  from  twelve  to  fifteen 
feet  in  the  wild  state,  but  under  cultivation  it  is  usually  dwarfed 
in  order  to  stimulate  the  greatest  possible  growth  of  the  young 
shoots.  These  yield  the  tender  new  leaves  so  desirable  in  tea- 
making.  It  will  grow  in  a  variety  of  climates,  but  the  sub-trop- 


256 


FOOD    INDUSTRIES 


ical  appears  to  be  the  best,  especially  in  sections  where  the  rain- 
fall  approximates   fifty   inches   annually.     The  plant   is   usually 


Fig.  65.— The  Tea  Plant.     (Courtesy  of  McCormick  &  Co.,  Baltimore,  Md.) 

placed  on  a  southern  exposure,  so  the  sunshine  will  protect  it 
from  cold,  and  in  soil  which  has  a  certain  water-retaining  prop- 
erty. In  China  most  of  the  tea  gardens  are  small,  each  farmer 


FOOD   INDUSTRIES  257 

producing  enough  for  the  consumption  of  his  own  family,  while 
the  surplus  is  sent  to  the  market.  Following  this  idea,  the 
United  States  Department  of  Agriculture  has  strongly  recom- 
mended the  growing  of  tea  on  the  farms  of  the  South  Atlantic 
and  Gulf  States.  With  very  little  trouble  and  expense,  the 
southern  farmer  could  at  least  raise  enough  tea  for  his  own  use, 
while  the  plant  itself  makes  a  hedge  well  worth  cultivating  for 
purely  ornamental  purposes.  Farmers  Bulletin,  No.  301,  "Home 
Grown  Tea"  gives  many  ideas  as  to  the  successful  cultivation 
and  manufacture  of  tea  in  the  United  States. 

In  modern  methods  of  cultivation,  the  plants  are  raised  from 
seeds  in  nurseries  and  are  set  out  in  their  permanent  home  in 
the  open  when  about  twelve  inches  high.  According  to  climate, 
soil,  etc.,  the  first  crop  is  borne  in  three  or  four  years,  and  from 
that  time,  the  shrub  "may  be  picked  at  regular  intervals.  It  is 
customary  to  occasionally  allow  the  plant  to  rest,  thus  insuring  a 
longer  life. 

General  Classification. — The  differences  in  the  tea  appearing 
on  the  market  do  not  depend  upon  the  variety  of  shrub,  but 
rather  on  the  size  of  the  leaf  and  the  way  in  which  it  is  treated 
during  manufacturing  processes.  According  to  the  method  of 
curing  it  is  designated  as : — 

I.  Black  tea,  which  has  a  dark,  dull  appearance. 

II.  Green  tea,  which  has  a  rather  brilliant  tinge  due  to  the 
retention  of  part  of  the  chlorophyl. 

For  a  long  period,  China  so  jealously  guarded  her  tea  gardens, 
that  her  green  and  black  teas  were  supposed  by  foreign  nations, 
to  be  produced  from  different  species  of  shrub.  That  this  idea 
was  false  was  finally  proved  by  Robert  Fortune,  who  travelled 
in  China  on  behalf  of  the  Horticultural  Society. 

Tea  is  also  classified  according  to  the  size  of  the  leaf  (Fig.  66). 

I.  Pekoe,  which  consists  of  the  three  young  shoots  at  the  tip 
and  are  known  as  flowery  pekoe,  orange  pekoe  and  pekoe  accord- 
ing to  their  size.    As  these  leaves  contain  the  least  fiber  and  the 
most  juice,  they  produce  the. finest  grade  of  tea. 

II.  Souchong  is  prepared  from  the  leaves  immediately  below 


258 


FOOD   INDUSTRIES 


the  pekoe  variety  and  makes  a  tea  of  popular  price.  Classes  I 
and  II  are  sometimes  mixed  when  the  product  is  known  as 
pekoe-souchong. 

III.  Congou   is   a   cheaper   variety   prepared    from   the   more 
fully  developed  leaves  below  the  souchong  size.     In  the  Ameri- 


/    Te 


ea 


c,     f'e/toc       c/,  *scor*Q 
>y    feecorjc/  } 


GO 


/4o  r? 


&   . 


Fig    66. 


can  market  this  term  is  sometimes  used  as  a  general  name  for 
China  Black  Teas. 

IV.  Bohea  is  a  name  frequently  applied  to  any  larger  leaf 
used  for  tea-making  than  the  congou  variety.  This  tea  is  no 
longer  found  in  our  market. 


FOOD   INDUSTRIES 


259 


Processes  of  Manufacture. — 

BLACK  TEA 
Leaves  picked. 
Withered  in  the  sun. 
Rolled  until  soft. 
Fermented. 
Fired. 
Sorted. 


GREEN  TEA 
Leaves  picked. 
Withered  in  pans. 
Rolled  until  soft. 
Withered  again. 
Sweated  in  bags. 
Slowly  roasted. 


Picking. — The  tea  leaves   are  plucked   entirely  by   hand,  the 
operation  generally  being  carried  on  by  women  and  children.    In 


Fig.  67. — Withering  Tea  Reaves.     (Courtesy  of  The  Spice  Mill  Publishing  Co.) 

China  and  Japan  there  are  several  harvests.  The  first  picking 
commences  about  the  middle  of  April  and  gives  delicate  pale 
green  leaves,  which  usually  command  a  high  price.  About  two 
weeks  later,  the  bush  is  again  ready  to  be  plucked  and  again  a 
third  and  fourth  picking  follow,  each  harvest  yielding  leaves  a 
little  lower  in  quality.  In  Ceylon  where  there  is  practically  no 
winter,  picking  takes  place  about  every  ten  or  twelve  days  the 
year  round. 

Withering. — \Yhether  small  or  large,  the  leaves  are  of  the  same 


200 


FOOD    INDUSTRIES 


general  structure.  All  consist  of  a  certain  amount  of  fibrous 
material  which  must  be  softened  by  rolling.  In  order  to  make 
this  operation  easier,  the  leaves  are  first  withered,  either  indoors 
or  by  exposure  to  the  sun,  until  part  of  the  moisture  has  evap- 
orated (Fig.  67).  In  good  weather  this  operation  takes  about 
eighteen  to  twenty-four  hours  but  when  cloudy  or  rainy,  artificial 
heat  must  be  used.  Withering  not  only  softens  the  leaves,  but 
assists  in  the  production  of  the  greatest  amount  of  enzyme  which 
is  needed  in  the  later  operation  of  fermentation. 


Fig.  68.— Rolling  Tea  Reaves.     (Courtesy  of  The  Tea  and  Coffee  Trade  Journal.} 

Rolling. — In  China,  rolling  is  still  done  very  largely  by  hand 
(Fig.  68).  The  worker  gathers  a  quantity  of  leaves  in  his  hands 
and  rolls  and  kneads  the  mass  with  a  very  similar  motion  to  that 
used  in  the  kneading  of  dough.  In  India  the  withered  leaves 
are  rolled  almost  entirely  by  machinery.  This  operation  bruises 
the  leaves,  takes  out  excess  moisture,  and  gives  the  characteristic 
twist  to  the  leaf. 

Fermentation. — Fermentation  is  the  most  important  part  of  the 


FOOD   INDUSTRIES  26 1 

preparation  of  black  tea,  for  its  influence  on  the  quality  and 
character  of  the  tea  is  very  great.  The  rolled  leaves  are  piled 
in  heaps  on  mats  or  frames  and  allowed  to  ferment  until  it  turns 
a  bright  copper  tint.  During  this  period,  the  tea  leaves  are  sub- 
jected to  the  influence  of  enzyme  action  and  important  chemical 
changes  take  place.  The  green  color  of  the  leaves  and  the  dis- 
agreeable odor  disappear,  and  a  fine  flavor  due  to  the  development 
of  essential  oils  is  acquired  in  proportion  to  the  amount  of  enzyme 
in  the  leaf.  According  to  the  investigations  of  Dr.  H.  H.  Mann 
"The  tannin  is  oxidized  during  fermentation  and  combines  with 
other  substances  in  the  leaf-forming  compounds,  some  of  which 
are  insoluble  in  water;  there  is,  therefore,  a  decrease  in  soluble 
tannin."  Experienced  judgment  is  necessary  to  determine  how 
far  fermentation  should  proceed ;  too  little  means  rawness  and  if 
carried  too  far,  much  of  the  delicate  flavor  is  lost. 

Firing. — Fermentation  is  checked  by  the  application  of  heat. 
The  leaves  are  sometimes  exposed  to  the  sun  then  fired  or  they 
may  be  immediately  fired,  care  being  taken  that  the  temperature 
is  sufficiently  high  to  remove  moisture,  but  not  high  enough  to 
drive  off  the  volatile  oils  which  have  been  developed  during 
curing. 

Sorting. — After  cooling,  tea  is  sorted  into  grades  by  sifting, 
is  packed  into  lead-lined  chests  and  is  ready  for  transportation. 

GREEN  TEA. — The  preparation  of  green  tea  differs  from  that 
of  black  tea  in  several  important  operations. 

I.  The   method   of   drying   is   different.      While   black   tea   is 
withered  in  the  sun,  the  leaves  for  green  tea  in  Japan  are  steamed 
until  they  lose  their  elasticity  and  in  China  are  heated  in  pans 
over  charcoal  fires.     In  a  few  minutes  the  leaves  become  soft 
and  pliable  and  are  ready  to  be  rolled. 

II.  After  rolling,  the  leaves  are  again  subjected  to  the  action 
of  a  slow,  steady  fire,  the  process  of  fermentation  being  omitted. 
The  chlorophyl  is,  therefore,  more  or  less  retained  and  tannins 
are  not  oxidized  to  insoluble  forms.     This  means  that  a  larger 
amount  of  tannic  acid  is  found  in  green  tea  when  used  as  a 


262  FOOD   INDUSTRIES 

beverage.  The  difference  in  flavor  is  entirely  due  to  fermenta- 
tion. 

Adulteration. — In  former  years  when  tea  was  expensive  and 
investigation  slack,  there  was  much  fraud  practiced,  especially  in 
the  Chinese  varieties.  The  adulteration  consisted  chiefly  in  the 
addition  of  foreign  leaves  and  in  facing.  The  leaves  of  the  ash, 
beech,  willow,  rose  and  buckthorn  were  frequently  mixed  with 
those  of  the  tea  plant.  Such  substitution  can  readily  be  detected 
with  the  microscope  as  tea  leaves  have  a  characteristic  appear- 
ance. Facing  consisted  in  treating  the  leaves  with  various  color- 
ing matter,  such  as  Prussian  blue,  indigo  or  plumbago.  By  such 
means  leaves  which  were  inferior  or  had  been  damaged  in  manu- 
facturing processes  or  during  a  sea  voyage,  could  be  improved 
in  color  and  general  appearance.  As  black  tea  does  not  need 
as  much  care  in  preparation  for  the  market,  attempts  were  also 
made  to  face  such  tea  and  sell  it  for  green  tea. 

Since  laws  have  been  passed  prohibiting  the  importation  of 
faced  tea,  there  is  practically  no  adulteration  to  be  found  in  the 
tea  sold  in  the  United  States.  Tea  growers  are  more  carefully 
watched,  government  inspection  is  more  rigid  and  competition 
is  much  greater  than  in  the  past.  For  a  long  period  the  Chinese 
were  the  chief  exporters  to  this  country,  but  the  rapid  growth 
in  the  popularity  of  the  India  and  Ceylon  teas  has  forced  China 
to  send  better  grades  to  hold  her  place  in  the  American  market. 

Tea  as  a  Beverage. — The  main  constituents  of  tea  to  be  con- 
sidered in  the  preparation  of  the  beverage  are  caffein  and  tannic 
acid.  Caffein  is  the  ingredient  which  gives  the  stimulating  prop- 
erty. It  belongs  to  a  class  of  substances  known  as  alkaloids. 

Caffein  is  not  present  in  the  leaf  but  is  probably  developed 
during  fermentation.  Just  below  the  boiling  point  of  water,  it 
is  remarkably  soluble.  Tannic  acid  is  not  particularly  soluble  at 
the  boiling  point,  but  will  become  so  on  prolonged  boiling.  These 
two  facts  must  be  taken  into  account  when  preparing  the  beverage. 
Caffein  is  a  mild  stimulant  and  is  desired  while  tannic  acid  so 
far  as  possible  should  be  avoided. 

General  Rules  for  Tea-Making. — Heat  freshly  drawn  water  to 


FOOD   INDUSTRIES  263 

the  boiling  point.  Pour  it  on  the  requisite  amount  of  tea,  which 
has  been  placed  in  a  previously  scalded  pot,  made  of  a  non-con- 
ducting material.  Allow  to  stand  in  contact  with  the  leaves  from 
three  to  five  minutes.  The  spent  leaves  should  not  be  used  again. 
Practically  all  the  stimulating  ingredient  has  been  removed  and 
that  which  is  left  is  deleterious  to  health. 

Tea  should  never  be  boiled;  the  delicate  aroma  is  lost  as  the 
essential  oils  volatilize.  Boiling  also  makes  soluble  the  tannin, 
too  much  of  which  is  undesirable. 

Composition  of  the  Beverage. — Beside,  caffein,  tannic  acid  and 
volatile  oil,  tea  contains  minute  amounts  of  nitrogenous  matter, 
fat,  dextrin,  fiber  and  mineral  matter. 

COFFEE. 

Historical. — The  early  history  of  the  cultivation  of  the  coffee 
bean  is  lost  in  antiquity,  but  it  is  to  Arabia  that  the  civilized 
world  is  indebted  for  the  knowledge  of  its  use  as  a  beverage. 
Tradition  gives  various  tales  of  its  introduction  into  Arabia,  one 
of  which  places  its  original  home  in  Abyssinia,  province  of  Caffa, 
from  which  it  is  supposed  to  have  received  its  name.  The 
Ethiopians  were  known  to  have  used  coffee  in  very  early  ages, 
but  with  that  nation  it  appears  to  have  served  as  a  food  rather 
than  a  beverage.  Wherever  its  origin  may  have  been,  Europeans 
discovered  its  use  in  Arabia  during  the  I5th  century.  Undoubt- 
edly the  knowledge  of  it  spread  very  largely  through  the  Arabian 
merchantmen,  who  added  the  coffee  bean  to  other  oriental  lux- 
uries, and  to  the  Mohammedan  pilgrims  who  flocked  annually  to 
Mecca.  Learning  to  drink  coffee  while  in  the  "Sacred  City," 
these  pilgrims  carried  back  with  them,  saddle-bags  of  the  coffee 
bean  to  all  parts  of  the  globe  professing  the  faith  of  Islam. 

It  reached  Constantinople  in  the  i6th  century  and  spread  from 
there  to  the  countries  bordering  on  the  Mediterranean,  finally 
being  introduced  into  London,  Paris  and  other  European  cities 
during  the  I7th  century. 

Originally  all  of  the  coffee  used  in  Europe  was  grown  in 
Arabia.  As  much  of  it  passed  through  the  port  of  Mocha,  it  was 
known  under  the  name  of  Mocha  coffee.  Later  coffee  was  grown 
18 


264  FOOD   INDUSTRIES 

in  the  European  colonies,  in  the  French  West  Indies  and  on  the 
island  of  Java.  Its  cultivation  soon  spread  to  Sumatra,  the 
Malay  Archipelago,  Ceylon,  the  Philippine  and  Hawaiian  Islands 
and  in  the  Western  World  to  Cuba,  Porto  Rico,  Mexico,  and  parts 
of  Central  and  South  America.  About  1740  it  was  planted  in 
Brazil  where  it  gradually  grew  to  be  so  important  an  industry, 
that  at  the  present  time  Brazilian  plantations  produce  three- 
quarters  of  the  total  supply  and  that  government  controls  the 
coffee  market  of  the  world. 

The  Coffee  Plant. — The  coffee  plant  is  a  very  beautiful  shrub 
attaining  a  native  growth  of  some  18-20  feet,  but  under  culti- 
vation, it  is  rarely  allowed  to  exceed  4-6  feet  in  height.  This 
dwarfing  the  plant,  increases  the  crop  and  facilitates  picking. 
The  leaves  are  a  fresh  green  color  expanding  outward  and  down- 


Fig.  69.— Coffee  Bean. 

ward,  giving  a  very  pleasing  appearance.  The  flowers  occurring 
in  clusters  are  white  in  color  and  have  an  odor  strongly  resem- 
bling jasmine.  The  flowers  and  fruit  which  are  frequently  called 
"the  cherries"  are  found  on  the  tree  at  the  same  time  and  in  all 
seasons,  in  various  stages  of  development.  It  is  from  these 
cherries  which  turn  a  dark  crimson  color  on  ripening,  that  the 
coffee  bean  is  obtained.  The  outer  part  of  the  cherry  is  fleshy 
similar  to  other  fruit,  while  within  are  two  seeds,  laid  face  to 
face,  covered  by  a  very  delicate  membrane  known  as  the  "silver 
skin"  and  an  outer  straw  colored  husk  called  "the  parchment" 
(Fig.  69).  The  main  processes  of  manufacture  consist  in  free- 
ing the  fruit  from  the  pulpy  matter  and  removing  the  two  inner 
skins  which  surround  the  seeds  These  seeds  are  in  reality  the 
unroasted  coffee  bean  of  commerce. 


FOOD   INDUSTRIES  265 

Cultivation. — The  coffee  shrubs  thrive  best  in  rich,  well-irri- 
gated soil  and  in  tropical  climate  where  the  rainfall  exceeds  75 
inches  per  annum.  They  are  propagated  from  seeds,  which  are 
planted  directly  in  the  fields  or  grown  in  wicker  baskets  in  nur- 
series until  18  inches  high,  when  they  are  transferred  to  their 
permanent  homes  in  the  open.  An  absence  of  frost  is  essential 
to  the  growth  of  the  plant  and  protection  from  wind  and  sun  is 
commonly  given  by  planting  shade  trees  between  the  young  coffee 
shrubs.  The  first  crop  of  any  importance  is  born  when  the  plant 
is  from  4  to  5  years  old,  and  with  care,  harvesting  may  be  con- 
tinued at  regular  seasons  for  20  years  or  more.  The  fruit  is 
ready  to  be  picked  when  it  is  dark  red  in  color  strongly  resemb- 
ling a  ripe,  red  cherry. 

Processes  of  Manufacture. — Harvesting. — In  Arabia,  the  fruit 
is  allowed  to  remain  on  the  tree  until  it  falls  off  of  its  own 
accord,  but  on  Brazilian  plantations,  which  are  by  far  the  largest 
in  the  world,  the  cherries  are  usually  picked  by  hand.  They 
are  allowed  to  fall  directly  on  the  ground  or  on  sheets  from  which 
they  are  later  raked  together,  and  a  first  rough  sorting  is  given 
before  they  are  packed  in  bags  to  be  removed  to  where  further 
treatment  is  given.  There  a  more  careful  sorting,  sifting  and 
winnowing  take  place,  and  the  berries  are  at  once  treated  with  the 
dry  or  wet  method  for  removal  of  the  pulp. 

Dry  Method. — The  berries  are  spread  out  on  drying  grounds 
where  they  are  left  exposed  to  the  sun  for  two  or  three  weeks, 
during  which  time  fermentation  takes  place  and  the  pulpy  mass 
gradually  dries.  It  can  then  be  removed  by  pounding  in  a  mortar 
or  by  passing  through  a  hulling  machine.  This  method  is  still 
used  in  Arabia  and  to  some  extent  on  modern  plantations  of 
Brazil,  many  planters  claiming  that  it  has  advantages  over  the 
modern  wet  process. 

Wet  Method. — Where  the  wet  process  is  used  inclined  canals 
are  frequently  built,  where  the  cherries  can  be  dumped  and 
carried  by  gravity  to  the  pulping  machine.  While  floating  down, 
imperfect  and  unripe  berries  rise  to  the  top  and  can  readily  be 


266 


FOOD   INDUSTRIES 


removed,   after   which   the   well   developed   berries   are   washed 
with  fresh  water  (Fig.  70). 

Pulping. — The  pulping  machines  are  of  various  types,  but  as  a 
rule  they  consist  of  a  revolving  cylinder  with  a  rough  surface 
which  faces  a  curved  metal  plate.  The  berry  is  crushed  between 
the  two  surfaces  in  such  a  manner  that  the  pulp  only  is  separated. 
The  interior  consisting  of  the  coffee  beans  with  the  two  coverings 
must  not  be  injured.  A  separation  is  made  by  sifting  and  all  im- 
perfectly pulped  must  be  reprocessed. 


Fig.  70.— Views  of  Coffee  Cultivation  and  Industry  of  Brazil.     Washing  Tanks. 
(Courtesy  of  The  Spice  Mill  Publishing  Co.) 

Fermentation. — The  beans  are  next  allowed  to  ferment  for 
twenty-four  to  seventy-two  hours  in  order  to  soften  and  loosen 
any  adherent  pulp.  The  essential  part  of  this  process  is  enzyme 
action  on  the  adhesive  substance,  but  as  to  its  effect  on  the  flavor 
of  the  coffee,  no  full  investigation  has  as  yet  been  made. 

Washing  and  Drying. — Successive  rinsings  with  water  finally 


FOOD   INDUSTRIES  267 

leave  the  parchment  covering  quite  free  from  adherent  pulp.  It 
is  now  known  as  "parchment  coffee"  and  must  be  subjected  to 
a  drying  process  in  order  to  remove  the  two  inner  coats  by 
friction.  Coffee  is  dried  in  most  places  out-of-doors,  on  the 
ground,  during  which  time  it  is  carefully  watched.  Too  slow 
or  too  rapid  drying  greatly  injures  the  flavor  of  the  coffee. 

Peeling. — The  two  coverings  can  now  be  readily  loosened  by 
an  ingenious  machine  which  cracks  the  parchment  and  inner  skin 
without  injuring  the  beans.  The  hulls  and  dust  are  separated  out 
by  winnowing,  leaving  the  coffee  beans  clean  and  ready  for  sort- 
ing. 

Sorting  and  Packing. — In  order  to  secure  uniformity,  the  beans 
are  separated  into  six  to  eight  grades.  They  are  sorted  first, 
according  to  size,  by  sifting  through  various  mesh  sieves ;  second, 
according  to  weight  by  being  subjected  to  strong  currents  of  air 
blowing  upward.  The  coffee  is  then  bagged  ready  for  removal 
to  the  shipping  port,  at  which  place  it  is  frequently  blended  and 
repacked  before  shipment. 

As  coffee  deteriorates  after  roasting,  that  process  is  usually 
carried  on  in  the  country  where  it  is  to  be  consumed.  On  arrival 
at  the  coffee-house,  the  raw  bean  is  subjected  to  a  thorough 
cleansing  process  to  remove  all  foreign  matter. 

Roasting. — The  cleaned  beans  are  run  into  a  revolving  oven 
and  are  subjected  to  a  temperature  of  200°  C.  In  the  production 
of  a  good  coffee  this  is  one  of  the  most  important  steps.  Count 
Rumford  in  an  essay  published  in  1812  says — "Great  care  must  be 
taken  in  roasting  coffee,  not  to  roast  it  too  much ;  as  soon  as  it 
has  acquired  a  deep  cinnamon  color,  it  should  be  taken  from  the 
fire  and  cooled;  otherwise  much  of  its  aromatic  flavor  will  be 
dissipated  and  its  taste  will  become  disagreeably  bitter.  The 
progress  of  the  operation  and  the  moment  most  proper  to  put  an 
end  to  it,  may  be  judged  and  determined  with  great  certainty; 
not  only  by  the  changes  which  take  place  in  the  color  of  the  grain, 
but  also  by  the  peculiar  fragrance  which  will  first  begin  to  be 
diffused  by  it  when  it  is  nearly  roasted  enough.  This  fragrance 
is  certainly  owing  to  the  escape  of  a  volatile,  aromatic  substance 


268 


FOOD   INDUSTRIES 


which  did  not  originally  exist  as  such  in  the  grain,  but  which  is 
formed  in  the  process  of  roasting  it." 

When  a  light  cinnamon  brown  is  desired,  coffee  is  allowed  to 
remain  in  the  oven  for  thirty  minutes  and  from  thirty-five  to 
forty  minutes,  if  a  heavy  chocolate  color  is  wanted.  It  is  then 
quickly  cooled  by  blasts  of  cold  air  and  is  ready  to  be  bagged  or 
boxed  for  the  market  (Fig.  71). 

The  effect  of  roasting  is  both  physical  and  chemical.  The 
physical  state  of  the  bean  is  changed  to  a  brittle  form,  in  which 


Fig.  71.— General  View  of  Coffee  Roasting  Room.     (Courtesy  of  The  Spice  Mill 
Publishing  Co.) 

it  can  more  easily  be  ground  or  pulverized.  Two  very  important 
chemical  changes  also  take  place ;  first,  the  formation  of  caramel 
which  greatly  improves  the  taste — this  flavor  can  readily  be, 
imitated  in  the  production  of  coffee  substitutes ;  second,  the  pro- 
duction of  an  oil  known  as  caffeol  to  which  the  aroma  of  roasted 
coffee  is  due.  As  this  oil  is  volatile,  coffee  should  be  consumed 
as  quickly  as  posible  after  roasting  and  should  never  be  pulver- 
ized until  at  the  time  of  the  preparation  of  the  beverage. 

Adulteraton. — Adulteration  of  coffee  has  consisted  in  the  ad- 


FOOD   INDUSTRIES  269 

dition  of  foreign  matter,  the  substitution  of  cheaper  substances, 
and  in  facing.  As  with  tea  facing,  the  addition  of  coloring 
matter  has  been  used  largely  to  conceal  poor  or  damaged  coffee 
or  to  make  inferior  varieties  appear  as  high  grade  material.  In 
former  years  an  imitation  bean  was  manufactured  and  occasion- 
ally mixed  with  coffee,  but  the  price  of  coffee  is  too  low  at 
present  to  make  such  substitution  profitable.  The  addition  of 
foreign  substances  was  much  more  practiced  with  ground  coffee 
than  that  sold  in  the  bean  form,  since  they  could  be  less  readily 
detected.  Cereals  of  various  kinds,  peas,  beans,  acorns  and  the 
like  have  from  time  to  time  been  added,  but  the  chief  adulterant 
has  been  found  to  be  chicory  which  is  the  kiln  dried  root  of  the 
wild  endive. 

In  recent  years  misbranding  has  been  found  more  frequently 
than  adulteration.  The  early  coffee  market  drew  its  supply 
almost  entirely  from  Arabia  and  from  the  islands  of  Java  and 
Sumatra.  These  coffees  were  known  on  the  market  as  Mocha 
and  Java.  As  the  coffee  industry  spread,  there  was  a  strong 
tendency  to  label  the  product  from  new  coffee  fields  as  Mocha 
and  Java,  since  those  two  names  had  taken  a  firm  hold  in  the 
minds  of  the  housewife.  The  passing  of  the  Food  and  Drug 
Act  of  June  30,  1906,  has  made  this,  also,  a  misdemeanor.  Al- 
though undoubtedly  much  coffee  is  still  on  the  market  not  prop- 
erly labeled,  there  is  a  strong  tendency  now  on  the  part  of  the 
manufacturers,  as  well  as  the  government,  to  have  coffee  imported 
under  its  own  name. 

Coffee  as  a  Beverage. — One  of  the  most  important  constituents 
of  coffee  and  the  ingredient  to  which  it  owes  its  stimulating  effect, 
is  the  alkaloid  caffein.  It  is  the  same  substance  as  is  found  in 
tea  but  occurs  in  a  rather  smaller  proportion,  approximately  I 
to  2  per  cent,  being  found  in  the  unroasted  bean.  Tannic  acid 
is  also  found  with  a  larger  amount  of  other  substances  as  fat, 
gum,  fiber,  sucrose,  dextrin,  reducing  sugar  and  mineral  matter. 
As  coffee  contains  volatile  oils,  every  effort  should  be  made  to 
retain  them,  in  the  preparation  of  the  beverage,  or  much  of 
the  aroma  and  flavor  will  be  lost. 


270  FOOD   INDUSTRIES 

Coffee  Extracts. — In  recent  years,  products  have  been  found 
on  the  market  called  coffee  extracts.  They  consist  essentially 
of  a  coffee  solution  from  which  the  water  has  been  evaporated 
in  vacuo  and  the  resulting  mass,  dried  and  ground.  When 
added  to  boiling  water,  they  are  supposed  to  have  the  original 
consistency  of  coffee  solution. 

COCO. 

Historical. — Coco  was  not  known  to  the  European  nations  until 
after  the  discovery  of  the  Western  World.  On  his  return  from 
the  third  voyage  to  America,  Columbus  was  supposed  to  have 
carried  back  with  him  to  Spain,  the  coco  bean,  as  a  curiosity  from 
the  newly  discovered  land.  It  was  introduced  into  Europe  in 
1528  by  Cortez  after  his  conquest  of.  Mexico.  The  explorer 
found  the  natives  of  the  new  land  using  the  roasted  bean,  ground 
and  mixed  with  maize  meal,  moistened  with  the  sweet  juice  of  the 
maize  stalk  and  flavored  with  vanilla  and  various  spices.  It  was 
known  to  them  as  chocolatl  and  was  considered  to  be  highly 
nutritious  as  well  as  a  beverage  of  great  delicacy.  Evidently 
it  was  also  held  in  high  esteem  by  the  Europeans  for  the  tree 
from  which  the  fruit  is  obtained,  was  known  to  them  as  "Theo- 
broma, — food  for  the  Gods."  Although  so  highly  prized,  its 
use  spread  very  gradually  in  Europe  and  it  is  not  until  recent 
years,  that  it  has  grown  considerably  in  popularity.  Possibly 
this  is  due  to  the  fact  that  tea  is  used  so  extensively  in  the 
British  Isles  and  coffee  in  the  continental  countries.  Coco  was 
first  introduced  into  the  States  by  the  fishermen  of  Gloucester, 
and  its  use  has  increased  to  so  great  an  extent  that  one-fifth  of 
the  world's  crop  is  now  consumed  in  the  United  States. 

Cultivation. — Coco  is  the  fruit  of  a  tropical  tree  commonly 
known  as  the  coco  tree  although  it  belongs  botanically  to  the 
species  cacao,  the  most  commonly  used  being  the  variety  theo- 
broma  cacao.  Thriving  only  in  tropical  climate,  20°  both  north 
and  south  of  the  equator,  its  cultivation  is  very  limited.  Only 
those  localities  of  America  and  Africa  with  their  neighboring 
islands,  that  have  well-watered,  well-drained  soils  and  plenty  of 
rainfall,  can  be  utilized  for  the  growing  of  the  tree.  The  West- 


FOOD   INDUSTRIES 


271 


ern  World  produces  by  far  the  largest  part  of  the  world's  crop, 
Ecuador  and  Brazil  being  the  largest  exporting  countries. 
Mexico  still  produces  the  greatest  amount  of  coco,  but  uses  most 
of  it  for  her  own  consumption. 

The  coco  tree  is  grown  from  seeds  either  planted  directly  in 
the  fields  or  in  nurseries.  It  attains  an  average  height  of  about 
20-30  feet  and  bears  small,  red,  wax-like  flowers  which  appear 
either  singly  or  in  clusters,  along  the  trunk  and  main  branches  of 


Fig.  72.— Pods  and  Leaves. 
(Copyrighted  by  Walter  Baker  &  Co  ,  and  used  with  their  permission.) 

the  tree.  The  fruit  is  a  pod  some  8-10  inches  long,  3-4  inches 
thick  (Fig.  72).  It  is  when  ripe,  either  lemon  color  or  chocolate 
brown,  according  to  the  variety,  and  has  a  thick  tough  rind  en- 
closing a  mass  of  cellular  tissue.  Embedded  in  the  pulpy  matrix 
are  some  forty  or  more  coco  beans  which  are  covered  with  a 
thin  shell  greatly  resembling  an  almond  (Fig.  73).  The  beans 
are  arranged  in  five  longitudinal  rows.  The  tree  begins  to  bear 
fruit  when  four  or  five  years  old  and  continues  to  the  age  of 
forty.  While  blossoms  and  fruit  are  to  be  found  on  the  tree, 
at  the  same  time  and  in  all  seasons,  there  are  two  main  crops 


272 


FOOD   INDUSTRIES 


gathered  yearly,  generally  in  June  and  December,  although  this 
varies  in  different  localities. 

Processes  of  Manufacture. — Picking. — The  pods  are  picked, 
when  fully  ripe,  either  by  hand  or  with  a  knife  fastened  to  a 
long,  bamboo  pole.  Great  care  is  necessary,  that  the  buds  and 
blossoms  which  lie  next  the  fruit  are  not  injured. 

Decomposition  of  Pod. — As  the  rind  of  the  pods  when  picked, 
is  exceedingly  woody  and  tough  and  would  be  difficult  to  cut, 
they  are  laid  on  the  ground  in  heaps  and  allowed  to  decompose 
for  twenty-four  hours,  or  until  the  rind  has  become  leathery. 
They  are  then  sorted  according  to  the  degree  of  ripeness  and 


Fig-  73- — Section  Coco  Fruit 

are  cut  open  with  a  sharp  cutlass.     The  pulp  and  coco  beans, 
still  within  their  shell,  can  readily  be  removed. 

Fermentation. — As  a  considerable  amount  of  the  soft  pulp 
still  clings  to  the  beans,  it  is  necessary  in  order  to  free  them,  to 
allow  fermentation  to  take  place.  This  process  is  carried  out  by 
heaping  the  beans  on  the  floor  where  they  are  allowed  to  sweat, 
by  burying  them,  or  by  the  use  of  enclosed  sweating  boxes  where 
they  remain  for  several  days.  The  seeds  are  frequently  turned 
to  insure  regular  sweating,  great  care  being  also  given  to  keep 


FOOD   INDUSTRIES  273 

the  temperature  from  rising  too  high.  Both  alcoholic  and  acetic 
fermentation  take  place  and  several  important  changes  occur. 
The  germinating  power  of  the  seed  is  arrested;  the  adherent 
pulp  is  loosened;  color  develops  and  an  exceedingly  bitter  taste 
is  modified  so  the  flavor  is  greatly  improved;  the  beans  are  less 
liable  to  be  attacked  by  mold  and  are  in  the  best  form  for  dry- 
ing. 

Washing  and  Drying. — When  fermentation  is  complete  the 
beans  are  sometimes  washed  before  drying.  Washing  is  carried 
out  by  placing  them  in  sieves  or  troughs,  where  they  are  thor- 
oughly scrubbed  and  rinsed,  to  remove  all  organic  matter  that 
may  be  clinging  to  them.  Whether  they  are  washed  or  not,  the 
coco  bean  must  pass  through  a  drying  process.  This  is  accom- 
plished by  the  heat  of  the  sun,  whenever  possible,  or  in  drying 
houses  which  are  heated  by  artificial  means.  In  out-of-door 
drying  some  ten  days  or  more  are  required,  indoor  drying  is 
complete  in  less  time.  In  some  countries  coloring  matter  is  used 
and  the  practice  of  polishing  the  bean  after  drying  is  frequently 
performed.  The  coco  is  now  ready  to  be  bagged  and  shipped 
to  the  markets  of  the  world. 

When  received  by  the  manufacturer  coco  is  cleaned,  sorted 
and  roasted. 

Roasting. — As  in  the  case  of  coffee,  this  process  must  be  care- 
fully guarded  to  insure  the  development  of  the  desired  flavor; 
too  much  heat  means  bitterness  and  too  little  leaves  the  coco 
with  a  crude  undeveloped  taste.  The  process  is  usually  carried 
out  in  large  iron  drums,  heated  to  from  125°- 145°  C.  and  con- 
stantly kept  in  motion.  During  the  roasting  the  thin  husks  of 
the  seeds  become  brittle  and  are  so  loosened,  that  afterwards  they 
can  easily  be  removed;  the  aroma  is  increased;  the  bitter  taste 
is  still  further  modified  and  the  starch  is  partially  dextrinized. 
When  sufficiently  roasted,  coco  is  quickly  cooled  in  order  to 
prevent  the  loss  of  the  aroma. 

Crushing. — The  roasted  seeds  are  next  run  through  a  machine 
called  the  cracker.  This  frees  the  outer  shell  from  the  inner 
parts  which  are  known  as  coco  nibs.  A  separation  of  shells, 


274 


FOOD    INDUSTRIES 


nibs  and  germs  is  effected  by  sieves  and  a  machine  of  special 
device.  As  the  shells  retain  the  flavor,  they  are  sold  and  used 
for  the  preparation  of  a  cheap  beverage.  The  nutritive  value  is 
not  great,  but  they  make  a  satisfactory  drink  for  people  of  weak 
digestion.  The  coco  nibs  are  used  for  the  preparation  of  the 
commercial  chocolate  and  coco. 


Fig.  74. — Grinding  Room. 
(Copyrighted  by  Walter  Baker  &  Co.,  and  used  with  their  permission.) 

Preparation  of  Chocolate. — The  coco  nibs  are  ground  into  a 
paste  by  a  series  of  revolving  stones,  arranged  in  pairs  and 
slightly  heated  to  assist  in  liquefying  the  coco.  While  in  a  semi- 
fluid condition,  the  paste  is  moulded  into  cakes  and  allowed  to 
harden.  It  may  be  sold  in  this  form  as  plain  chocolate  or  the 
ground  nibs  may  be  passed  into  a  mixer  and  finely  ground  sugar, 
spices,  vanilla  and  other  flavors  may  be  incorporated.  After 
moulding,  it  is  placed  on  the  market  as  sweet  chocolate  or  as 


FOOD   INDUSTRIES 

milk  chocolate,  if  condensed  or  powdered  milk  has  also  been 
added. 

Preparation  of  Coco. — As  the  coco  nib  is  too  rich  in  fat  for 
ordinary  purposes,  sometimes  approximately  one-half  of  the  total 
weight,  it  is  customary  to  remove  a  portion  of  it.  The  product 
is  then  known  as  coco.  In  the  United  States  this  is  chiefly  car- 
ried on  by  running  the  ground  nibs,  while  in  the  semi-liquid 
form,  directly  from  the  grinder  into  an  hydraulic  press,  which 
removes  some  60-70  per  cent,  of  the  fat.  It  is  then  allowed  to 
cool  after  which  it  is  reduced  to  a  powder  and  boxed.  The  ex- 
tracted fat  is  clarified  and  made  into  coco-butter.  As  coco-butter 
does  not  readily  turn  rancid  if  carefully  stored,  it  is  used  largely 
in  pharmacy,  for  candy-making  and  in  the  preparation  of  cos- 
metics, perfumes,  pomades  and  soft  toilet  soaps. 

Adulteration. — Coco  preparations  have  been  much  subject  to 
adulteration.  In  order  to  increase  the  bulk  and  weight,  sugar 
and  various  starches  have  been  frequently  added,  while  sand, 
clay,  the  ground  shells  of  the  coco-bean,  powdered  roasted 
acorns,  chestnuts  and  other  substances  of  organic  and  inorganic 
origin  have,  from  time  to  time,  been  found.  Fats  of  cheaper 
variety,  as  lard  or  coconut  oil,  are  used  to  restore  the  normal 
percentage  of  fat  after  coco-butter  has  been  removed.  In 
cheaper  grades  of  chocolate,  glucose  is  sometimes  used  in  place 
of  sugar,  while  inferior  flavorings  and  coloring  matter  are  fre- 
quently added. 

As  a  Beverage. — Coco  not  only  furnishes  the  material  for  a 
refreshing  and  exhilarating  beverage,  but  is  a  food  of  great 
nutritive  value.  This  may  readily  be  seen  by  the  average  com- 
position of  the  coco  bean  as  given  by  Payen. 

Fat 50 

Starch TO 

Albuminoids 20 

Water 12 

Cellulose 2 

Mineral  matter 4 

Theobromine 2 

Theobromine  which  is  responsible  for  the  stimulating  effect  of 


276  FOOD   INDUSTRIES 

coco,  is  closely  related  chemically  to  the  alkaloid  caffein,  which 
occurs  in  tea  and  coffee  and  has  a  similar  physiological  effect. 
The  presence  of  so  high  a  percentage  of  fat,  protein  and  car- 
bohydrate not  only  makes  coco  of  greater  nutritive  value  than 
tea  or  coffee,  but  both  soluble  and  insoluble  portions  become  a 
part  of  the  beverage.  This  is  not  true  of  tea  or  coffee  where 
only  the  constituents  soluble  in  hot  water  are  obtained. 

As   chocolate    is    a   concentrated    food,    it    frequently   causes 
biliousness  when  indulged  in  too  freely. 


CHAPTER  XXL 


SPICES  AND  CONDIMENTS. 

The  word  condiment  is  applied  to  products  which  possess  no 
nutritive  value,  but  are  added  to  food  to  make  it  more  palatable 
and  to  stimulate  digestion.  They  may  be  either  organic  or  in- 
organic. 

Sodium  chloride  or  common  salt,  the  most  necessary  to  man 
and  used  to  the  largest  extent,  is  inorganic.  It  appears  to  be  the 
one  item  of  food  found  in  the  diet  of  all  nations  and  every  race 
from  the  earliest  times,  the  chlorine  being  utilized  by  the  system 
in  the  formation  of  hydrochloric  acid  of  the  gastric  juice,  while 
the  sodium  is  needed  in  the  production  of  the  bile.  Its  use  is 
particularly  important  among  people  whose  diet  consists  largely 
of  vegetables  and  vegetable  products. 

Salt  is  procured  from  natural  deposits  of  sodium  chloride  in 
the  form  of  solid  crystals,  from  natural  or  artificial  brine  wells 
and  from  the  sea  by  the  process  of  evaporation.  Formerly  much 
of  our  salt  came  from  the  Bahama  Islands.  These  islands  are 
of  coral  origin  and  possess  comparatively  little  vegetation.  Small 
pools  can  be  found  in  many  places  where  the  sun  in  time  evap- 
orates the  water,  leaving  a  deposit  of  salt  which  could  be  sent  to 
the  market  The  product  was  known  as  Turks  Island  Brand. 
Natural  brine  wells  are  underground  streams  which  may  be  the 
result  of  sweet  water  percolating  through  salt  soil,  or  they  may 
have  come  from  a  body  of  salt  water.  Artificial  brine  wells  have 
been  made  by  man  by  running  water  into  a  salt  deposit.  The 
brine  may  then  be  pumped  to  the  surface  which  is  an  easier 
method  of  obtaining  the  salt  than  by  digging. 

A  large  part  of  the  salt  on  the  American  market  to-day  comes 
from  natural  brine  wells  in  the  vicinity  of  Syracuse,  New  York, 
and  along  the  borders  of  Lake  Erie.  They  were  discovered  as 
early  as  1654  by  the  French  Jesuits,  who  found  the  Iroquois  and 
other  Indian  tribes  making  use  of  the  salt.  Michigan  in  the 
southern  part,  Ohio  and  Kansas  are  also  rich  in  saline  deposits, 


278  FOOD    INDUSTRIES 

and  much  is  procured  from  Utah  on  the  shores  of  Great  Salt 
Lake. 

In  the  process  of  preparing  salt  for  the  market,  the  brine  is 
passed  through  a  succession  of  heaters  with  an  increasing  range 
of  temperature.  By  this  means  many  of  the  impurities  are  pre- 
cipitated and  can  be  filtered  off.  The  brine  is  then  run  into 
evaporators  where  the  water  volatilizes  and  the  salt  deposits. 
Since  the  salt  still  contains  impurities  it  is  purified  by  recrystalli- 
zation  from  water.  It  is  then  dried,  sifted  into  grades  and  packed 
in  bags,  barrels  or  other  packages. 

SPICES. 

Spices  comprise  all  aromatic  vegetable  substances  which  may 
be  added  to  food,  principally  to  make  it  more  palatable.  They 
have  been  used  from  the  earliest  known  eras  of  civilization  and 
have  played  an  important  part  in  the  discovery  of  a  water  pas- 
sage to  the  far  east,  in  the  colonizaton  of  the  East  Indies,  and 
in  the  opening  up  of  these  countries  to  western  civilization  and 
to  western  trade. 

The  tropical  parts  of  Asia  have  given  to  the  world  by  far  the 
greatest  variety  and  quantity  of  spices,  such  as  pepper,  cinna- 
mon, nutmeg,  mace,  cloves,  turmeric,  ginger  and  cassia.  The 
tropical  countries  of  America  have  added  several  new  varieties  to 
the  list,  >as  cayenne  pepper  and  vanilla.  The  West  Indies  is 
celebrated  for  ginger  and  is  also  the  home  of  the  pimento.  From 
Africa,  grains  of  Paradise,  are  obtained. 

All  spice  plants  are  grown  in  tropical  climates,  latitude  25°  N. 
and  25°  S.  of  the  equator,  where  there  is  considerable  rainfall 
and  soil  with  water  absorbing  properties.  Most  of  these  flavoring 
plants  are  found  on  islands  in  close  proximity  to  the  sea.  Spices 
are  obtained  from  different  parts  of  the  plant ;  dried  fruit  as 
pepper,  pimento,  nutmeg,  mace;  dried  bark  as  cinnamon  and 
cassia ;  flower  buds  as  cloves ;  the  root  as  ginger ;  seeds  as  cara- 
way ;  leaves  as  sage,  thyme,  etc.  Many  of  these  owe  their  power 
to  essential  oils  which  in  some  cases  are  extracted  and  used  as 
flavoring  extracts.  The  flavor  of  others  is  due  to  esters  and  to 
alkaloids. 


FOOD   INDUSTRIES  279 

Uses. — While  the  principal  use  of  spices  is  to  add  flavor  to 
food  and  beverages,  this  is  by  no  means  their  only  service  to  man. 
Many  are  used  in  perfumery,  in  soap  making  and  in  the  manu- 
facture of  incense.  Several  varieties  are  utilized  in  medicine 
chiefly  to  disguise  a  disagreeable  flavor;  turmeric  is  used  in 
dyeing  and  others  in  the,  various  arts.  In  Egyptian  days,  they 
were  utilized  for  embalming  all  the  distinguished  dead. 

While  spices  have  been  used  from  early  ages  in  connection 
with  food  for  the  sake  of  the  various  flavors  that  they  yield, 
it  has  been  left  to  modern  times  to  discover,  that  they  also  assist 
in  the  preservation  of  the  material  to  which  they  have  been 
added.  This  is  due  to  the  fact  that  they  contain  antiseptic  prin- 
ciples. 

Spices  as  Preservatives. — That  spices  are  useful  as  preservatives 
may  readily  'be  detected  with  such  food  products  as  sausages 
and  mince  meat.  Mince  meat  as  a  rule,  has  for  its  chief  con- 
stituents chopped  meat  and  apples.  Meat  is  subject  to  decay 
by  bacterial  action  and  apples  furnish  an  excellent  food  for  mold 
and  yeast,  yet  it  is  a  well  known  fact  that  mince  meat  will  keep 
for  many  months.  Sausage  meat  is  subject  to  rapid  putrefaction 
but  in  winter  weather,  it  can  also  be  kept  for  a  length  of  time  on 
account  of  the  high  content  of  spices.  Fruit  cake  furnishes 
another  example.  It  can  be  held  for  an  indefinite  period  arid 
even  improves  with  age.  Spices  do  not  furnish  a  complete  pro- 
tection, however,  and  food  material  to  which  they  have  been 
added  should  not  be  allowed  to  stand  in  a  warm  place,  or  fermen- 
tation and  decay  will  set  in. 

Although  these  facts  have  been  common  knowledge  for  many 
years,  very  little  experimental  work  has  been  done,  as  to  the 
varieties  which  contain  the  best  antiseptic  properties  and  the 
amount  which  should  be  used.  Unfortunately  many  of  them 
are  irritating  to  the  mucous  membrane  and  when  used  in  excess 
are  harmful.  It  is  very  important,  therefore,  that  the  manu- 
facturer and  housewife  should  know  which  spices  may  be  used 
for  their  antiseptic  properties  and  what  the  physiological  effect 
is,  of  such  condiments.  To  the  experimental  work  of  Conrad 
19 


28O  FOOD    INDUSTRIES 

Hoffman  and  Alice  Evans,  the  authors  are  indebted  for  the  fol- 
lowing information.* 

That  ginger,  black  pepper  and  cayenne  pepper  do  not  prevent 
the  growth  of  micro-organisms  but  that  cinnamon,  cloves  and 
mustard  are  valuable  preservatives.  Nutmeg  and  allspice  delay- 
growth  but  cannot  be  considered  of  any  practical  importance,  since 
the  amount  used  in  cooking  is  too  small  to  preserve  food  for  any 
length  of  time.  Cinnamon,  cloves  and  mustard  are  almost  equal 
in  their  efficiency.  Cloves  when  used  in  large  enough  amounts 
to  prevent  growth  have  a  burning  taste  to  the  palate,  but  cinnamon 
and  mustard  are  particularly  valuable  as  they  are  palatable  even 
when  used  in  proportions  that  prevent  all  growth.  The  active 
antiseptic  constituents  of  mustard,  cinnamon  and  cloves  are  their 
aromatic  or  essential  oils.  Cinnamon  contains  cinnamic  aldehyde 
which  is  more  effective,  if  pure,  than  benzoate  of  soda. 

Commonly  Used  Spices. — Vanilla. — Vanilla  is  obtained  from  the 
fruit  of  a  climbing  orchid,  native  of  tropical  America,  but  now 
grown  in  Java,  Ceylon  and  other  parts  of  the  Orient.  It  was  used 
by  the  Aztecs  as  a  flavoring  agent  for  their  favorite  beverage 
chocolate,  before  the  discovery  of  America,  and  was  taken  to 
Europe  by  the  explorers  as  early  as  1510.  The  fruit  is  a  pod 
which  must  be  dried  and  cured  with  great  care  in  order  to  obtain 
the  desired  flavor.  The  characteristic  odor  is  developed  during 
the  process  of  fermentation  which  takes  place  while  drying.  The 
aroma  and  flavor  are  due  to  a  substance  known  as  vanillin  which 
gradually  crystallizes  out  from  the  fluid  of  the  pod.  The  well 
cured  pods,  either  whole  or  powdered,  may  be  found  on  the 
market  as  the  vanilla  bean  or  powder,  but  a  more  common  form 
is  the  extract  of  vanilla.  This  is  obtained  by  dissolving  out  the 
flavoring  material  by  the  use  of  alcohol. 

Modern  science  has  furnished  a  commercial  rival  to  vanilla 
extract  in  the  production  of  synthetic  product.  Vanillin  has  been 
largely  prepared  from  engenol,  a  substance  to  which  oil  of  cloves 
owes  it  characteristic  odor,  and  in  recent  years  much  has  also 
been  obtained  electrolytically  from  sugar. 

*  The  Use  of  Spices  as  Preservatives  by  Conrad  Hoffman  &  Alice  Evans.  Published 
in  Journal  of  Industrial  &  Engineering  Chemistry. 


FOOD    INDUSTRIES 


28l 


Pepper. — Various  spices  can  be  found  on  the  market  under 
the  general  head  of  pepper,  but  the  most  common  forms  are  black 
and  white  pepper.  Pepper  is  one  of  the  oldest  spices  known  to 
mankind  and  is  still  used  in  enormous  quantities.  Although  it  now 
sells  at  so  low  a  price  that  it  may  be  utilized  by  comparatively 
poor  people,  it  was  worth  its  weight  in  gold  during  the  days  of 
the  Roman  Empire.  The  high  price  in  the  Middle  Ages  led  the 
Portuguese  to  seek  a  water  route  to  the  far  east,  and  the  first 
vessel  that  sailed  around  the  Cape  of  Good  Hope  had  for  its 
object  the  finding  of  a  cheaper  way  to  procure  pepper. 


Fig-  75-— Pepper  Plantation  near  Singapore.     (Courtesy  of  The  Spice  Mill  Publishing  Co.) 

The  black  variety  is  prepared  from  the  dried,  unripe  berry 
of  a  vine  which  was  grown  first  in  Southern  India,  the  East 
Indies,  Siam,  Cochin  China  and  in  later  ages  in  the  West  Indies. 
For  a  long  period  the  Dutch  nation  controlled  the  trade  and  tried 
to  confine  its  cultivation  to  the  Island  of  Java  and  other  Dutch 
possessions. 

The  berry  is  gathered  before  it  is  fully  matured,  is  spread  out 
on  mats  for  several  days,  after  which  the  outer  skin  is  removed 
by  rubbing  with  the  hand.  It  is  then  cleaned  by  sifting  and  is 


.282  FOOD    INDUSTRIES 

usually  ground  before  being  placed  on  the  market.  \Yhite  pepper 
is  generally  supposed  to  be  produced  from  a  different  spice  but 
is  in  reality  the  same  fruit,  prepared  by  a  different  method.  It 
is  generally  considered  better  but  the  product  has  not  as  good  a 
flavor  and  is  more  expensive,  the  only  advantage  being  in  the 
appearance  (Fig.  75). 

Mustard. — The  mustard  most  commonly  used  is  obtained  by 
grinding  to  a  flour,  the  small  seeds  of  the  mustard  plant.  The 
plant  which  may  be  found  either  in  the  wild  state  or  under  cul- 
tivation has  a  wide  distribution  in  Europe,  northern  Africa, 
Asia,  the  United  States,  the  West  Indies  and  South  America. 
It  has  been  used  for  medicinal  purposes  from  remote  antiquity, 
but  appears  to  have  been  unknown  as  a  condiment  until  1829, 
when  a  resident  of  Durham,  England,  placed  it  upon  the  market, 
keeping  the  manufacturing  process  a  secret.  The  product  was 
given  the  name  of  Durham  Mustard,  a  brand  which  is  still 
found  in  the  market  of  to-day. 

The  two  most  common  varieties  of  seeds  used  at  present  are 
brown  and  yellow  in  color,  the  brown  yielding  the  highest  grade 
product.  Mustard  is  prepared  by  passing  the  interior  of  the 
seed  through  a  winnowing  machine,  for  the  removal  of  foreign 
material  and  crushing  the  grain  between  rollers,  after  which  the 
oil  is  removed  by  hydraulic  pressure.  The  cake  is  then  dried, 
powdered  and  bottled.  The  powder  is  frequently  mixed  with 
spices  and  oil  when  it  is  known  as  prepared  mustard.  Much 
adulteration  has  been  practiced  in  the  preparation  of  mustard, 
principally  in  the  addition  of  wheat  flour,  turmeric,  cayenne 
pepper,  etc. 

Cinnamon  and  Cassia. — Cinnamon  is  the  inner  bark  of  young 
shoots  of  a  certain  species  of  cinnamon  tree,  which  is  particularly 
rich  in  a  volatile  oil  known  as  oil  of  cinnamon.  It  is  apparently 
one  of  the  oldest  of  the  spices  used  by  man  and  was  the  first 
sought  after  in  the  oriental  voyages  of  the  early  merchantmen. 
The  shoots  are  cut  very  carefully  from  the  tree,  the  bark  is  slit 
longitudinally  and  is  removed  in  strips  by  special  knives.  The 
strips  are  *piled  in  heaps  and  allowed  to  ferment,  after  which  the 


FOOD    INDUSTRIES 


283 


epidermis  is  removed.  The  bark  shrinks  on  drying  and  is  known 
as  "the  quills."  These  are  then  put  up  in  bundles  ready  for  ex- 
portation (Fig.  76). 

Cassia  in  olden  times  was  obtained  entirely  from  the  bark  of 
other  varieties  of  cinnamon  trees.  It  was  thick,  comparatively 
coarse  and  was  generally  considered  inferior  to  cinnamon. 
Much  of  the  cassia  of  to-day,  however,  is  obtained  from  China 


Fig.  76.— Rolling  Cinnamon  Bark  into  Quills.     (Courtesy  of  the  Spice  Mill  Publishing  Co.) 

and  the  Dutch  West  Indies,  from  the  fragrant  bark  of  a  plant 
known  as  the  cassia.  It  has  a  much  more  pronounced  flavor  than 
cinnamon  and  is  frequently  used  as  an  adulterant. 

Cloves. — Cloves  are  the  unopened  flower  buds  of  an  exceed- 
ingly beautiful  evergreen  tree,  which  grows  mainly  in  the  Spice 
Islands.  They  were  known  to  the  ancients  and  were  considered 
an  important  article  of  trade  in  the  Middle  Ages.  The  curing 
process  is  very  simple.  After  picking,  the  buds  are  thrown  on 


284  FOOD    INDUSTRIES 

the  ground  on  grass  mats  and  are  allowed  to  dry  in  the  sun,  care 


Fig-  77-— Clove  Tree  of  Zanzibar.     (Courtesy  of  The  Spice  Mill  Publishing  Co.) 

being  taken  to  shelter  them  from  the  dew  at  night.    In  about  one 


FOOD   INDUSTRIES  285 

.•> 

week,  they  are  ready  to  be  packed  for  export.  Cloves  contain 
about  16  per  cent,  of  a  volatile  oil,  which  can  easily  be  removed 
and  is  of  considerable  value.  It  is  used  largely  in  perfumery  and 
in  soaps  (Fig.  77). 

Allspice. — Allspice,  known  to  the  Spaniards  as  pimento,  is  the 
dried,  unripe  fruit  of  an  evergreen  tree  native  to  the  West  Indies, 
Mexico  and  South  America.  The  chief  supply  comes  from 
Jamaica.  The  name  allspice  has  been  given  on  account  of  the 
fact  that  its  very  fragrant  odor  and  flavor  appears  to  be  a  com- 
bination of  those  obtained  from  cinnamon,  cloves  and  nutmeg. 
The  fruit  is  picked  before  it  is  ripe,  is  dried  in  the  sun  and 
usually  ground  on  common  burr-stones.  It  is  used  frequently 
for  medicinal  purposes  to  disguise  the  taste  of  nauseous  drugs, 
and  in  the  tanning  of  some  kinds  of  leather.  Allspice  yields  a 
volatile  oil  on  distillation  which  is  used  as  a  flavoring  in  alcoholic 
solutions. 

Nutmeg  and  Mace. — Nutmeg  is  the  dried  kernel  of  the  fruit 
of  a  tropical  tree  somewhat  resembling  an  orange  tree.  It  is 
native  to  the  Malay  Archipelago,  but  is  also  grown  largely  in 
Asia,  Africa,  South  America  and  the  West  Indies.  The  fruit  is 
gathered  when  fully  ripe  and  the  outer  part  is  discarded.  The 
seeds  are  then  dried  in  the  sun  or  by  artificial  means.  The  thin 
outer  seed  coat  is  broken,  and  the  kernal  or  nutmeg  is  ready  to 
be  cleaned  and  packed.  Nutmeg  is  exported  in  the  unground 
state  in  order  to  retain  the  flavor.  The  inner  envelope  which 
surrounds  the  nut  is  also  dried,  and  exported  under  the  name  of 
mace. 

Ginger. — Ginger  is  the  only  spice  taken  from  the  root.  The 
original  home  of  the  plant  is  supposed  to  be  China,  but  it  is  now 
grown  in  many  tropical  countries.  The  West  Indies  produce  an 
excellent  quality,  that  from  Jamaica  usually  being  considered  the 
best.  The  root  may  be  left  unpeeled  when  it  is  simply  dried  in 
the  sun,  or  it  may  be  peeled  after  having  been  scalded.  Preserved 
ginger  is  prepared  very  largely  in  China,  especially  Canton. 
After  being  peeled,  the  ginger  is  treated  with  a  boiling  solution 


286 


FOOD    INDUSTRIES 


of  sugar,  after  which  it  is  packed  in  jars  or  sent  to  the  market 
in  the  dry  state  (Fig.  78). 

Adulteration. — In  former  years,  no  article  connected  with  our 
food  supply  was  more  largely  subject  to  adulteration  than  spices, 
especially  when  they  were  placed  on  the  market  in  the  ground 
condition.  Spices  of  a  good  quality  were  usually  high  in  price, 
and  many  cheap  materials  could  be  found  which  to  some  extent 
resembled  the  real  article.  They  were  used  frequently  as  dil- 


Fig.  78.— Digging  and  Peeling  Ginger  in  the  Fields— Ginger  Plantation,  Jamaica. 
(Courtesy  of  The  Spice  Mill  Publishing  Co.) 

uents  and  to  some  extent  as  complete  substitutes.  According  to 
Bulletin  13  of  the  United  States  Department  of  Agriculture,  a 
profitable  business  for  many  years  was  carried  on  in  manufactur- 
ing of  products  known  as  spice  mixtures.  They  consisted  of  a 
combination  of  various  materials  as  ground  coconut  shells,  wheat 
flour,  crackers,  charcoal,  coloring  and  mineral  matter,  yellow 
cornmeal,  mustard,  husks,  sawdust  and  other  odds  and  ends. 

Much    misbranding    has    also    been    found    especially    among 
flavoring  extracts. 


FOOD   INDUSTRIES  287 

VINEGAR. 

Vinegar  is  used  very  largely  in  connection  with  food,  the  same 
as  spices,  to  give  flavor  and  as  a  preservative.  Such  articles  as 
pickles  depend  largely  upon  vinegar  for  their  keeping  quality. 
It  does  not  contain  antiseptics  as  do  the  spices,  but  owes  its  pre- 
servative value  to  the  acetic  acid  which  inhibits  the  growth  of 
putrefactive  bacteria. 

The  manufacture  of  vinegar  has  been  treated  under  the  Fer- 
mentation Industries.  See  Chapter  XII. 


BIBLIOGRAPHY. 


CHAPTER  I.— FOOD  PRINCIPLES. 
Sherman,  Henry  C. — Chemistry  of  Foods  and  Nutrition. 
Jordan,  Whitman  H. — Principles  of  Human  Nutrition. 
Vulte,  H.  T.— Household  Chemistry. 
Perkin  and  Kipping. — Organic  Chemistry. 
Thorpe. — Dictionary  of  Applied  Chemistry. 
Haas  and  Hill. — An  Introduction  to  the  Chemistry  of  Plant  Products. 

CHAPTER  II.— WATER. 
Mason,  William  P.— Our  Water  Supply. 
Richards  and  Woodman. — Air,  Water  and  Food. 
Leffmann,  Henry. — Examination  of  Water. 
Frankland,  E. — Water  Analysis. 
Wanklyn  and  Chapman. — Water  Analysis. 
Harrington,  Charles. — Practical  Hygiene. 
Thorpe. — Dictionary  of  Applied  Chemistry. 
Buchanan,  E.  D.  and  R.  E. — Household  Bacteriology. 
Schultz,  Carl  H.— Mineral  Waters. 

CHAPTERS  III  AND  IV.— OLD  AND  MODERN 

MILLING  'PROCESSES. 

Doudlinger,  Peter  Tracy.— The  Book  of  Wheat. 
Edgar,  William  C.— Story  of  a  Grain  of  Wheat. 
Amos,  Percy  A. — Processes  of  Flour  Manufacture. 
Grant,  James. — The  Chemistry  of  Breadmaking. 
Wiley,  Harvey  W. — Foods  and  Their  Adulteration. 
Bulletin    No.    57,    Agricultural    Experiment    Station,    Ottawa,    Canada. — 

Quality  in  Wheat. 

Trade  Paper.— The  Northwestern  Miller. 
Encyclopedias. — Britannia,  International. 

CHAPTERS  V  AND  VI.— CEREALS   AND   BREAKFAST  FOODS. 

Burtt-Davy,  Joseph. — Maize :  Its  History,  Cultivation,  Handling  and  Uses. 

Freeman  and  Chandler. — The  World's  Commercial  Products. 

Harrington,  Charles. — Practical  Hygiene. 

Wiley,  Harvey  W. — Foods  and  Their  Adulteration. 

Ward,  Artemus. — The  Grocers  Encyclopedia. 

Bulletin  No.  131,  Agricultural  Experiment  Station,  Orono,  Maine. — Indian 

Corn  as  Food  for  Man. 
Bulletin  No.  118,  Agricultural  Experiment  Station,  Orono,  Maine. — Cereal 

Foods. 


FOOD   INDUSTRIES  289 

Bulletin  No.  65,  Agricultural  Experiment  Station,  Orono,  Maine. — Coffee 
Substitutes. 

Bulletin  No.  211,  State  Agricultural  College  Experiment  Station,  Michi- 
gan.— Breakfast  Foods. 

Bulletin  No.  162,  Dept.  of  Agriculture,  Ontario  Agricultural  College, 
Ontario,  Canada. — Breakfast  Foods. 

Farmers  Bulletin  No.  249,  U.  S.  Department  of  Agriculture,  Washington, 
D.  C.— Cereal  Breakfast  Foods. 

Farmers  Bulletin  No.  417,  U.  S.  Department  of  Agriculture,  Washington, 
D.  C.— Rice  Culture. 

Encyclopedias. — Britannia,  International. 

CHAPTER  VII.— UTILIZATION  OF  FLOUR. 
Jago,  W.  and  W.  C. — Technology  of  Breadmaking. 
Grant,  James. — The  Chemistry  of  Breadmaking. 
Buchanan,  E.  D.  and  R.  E. — Household  Bacteriology. 
Conn,  H.  W. — Bacteria,  Yeasts  and  Molds  in  the  Home. 
Jordan,  E.  O. — General  Bacteriology. 
Farmers  Bulletin  No.  389,  U.  S.  Department  of  Agriculture,  Washington, 

D.  C. — Bread  and  Breadmaking. 
The    National    Geographic    Magazine,    March,    1908. — Making    Bread    in 

Different  Parts  of  the  World. 

CHAPTER  VIII.— LEAVENING  AGENTS. 
Thorpe. — Dictionary  of  Applied  Chemistry. 
Smith,  Alexander. — General  Inorganic  Chemistry. 
Harrington,   Charles. — Practical   Hygiene. 
Bulletin  No.   13,   Part  Fifth,  U.  S.  Department  of  Agriculture,   Division 

of  Chemistry. — Baking  Powders. 
Bulletin     No.     52,     Agricultural     Experiment     Station,     Florida. — Baking 

Powders. 

CHAPTER  IX.— STARCH   AND  ALLIED  INDUSTRIES. 
Sadtler,  Samuel. — Handbook  of  Industrial  Organic  Chemistry. 
Thorp,  Frank  H. — Outlines  of  Industrial  Chemistry. 
Thorp. — Dictionary  of  Applied  Chemistry. 
Olsen,  John  C. — Pure  Foods. 
Humphrey,    H.     C. — Descriptive     Paper — The     Corn     Products     Refining 

Industry. 
Bulletin  No.  202,  U.  S.  Department  of  Agriculture,  Washington,  D.  C. — 

Digestibility  of  Starch  of  Different  Sorts  as  Affected  by  Cooking. 
Bulletin,  Department  of  Agriculture,  North  Carolina. — Starches  Used  in 

Cotton  Mills  and  Their  Adulterations. 


290  FOOD   INDUSTRIES 

CHAPTER  X.— THE  SUGAR  INDUSTRY. 
Sadtler.  Samuel  P. — Handbook  of  Industrial  Organic  Chemistry. 
Thorp,  Frank  H. — Outlines  of  Industrial  Chemistry. 
Thorpe. — Dictionary  of  Applied  Chemistry. 
Wiley,  Harvey  W. — Foods  and  Their  Adulteration. 
Durr,  Noel. — Sugar  and  the  Sugar  Cane. 

International  Library  of  Technology. — Manufacture  of  Sugar. 
The  School  of  Mines  Quarterly,  Columbia'  University,  April,  1911. — The 

Chemistry  of  Raw  Sugar  Production;   Sugar  Refining. 
The   School  of   Mines   Quarterly,   Columbia  University,   January,    1913. — 

Manufacture  of  Raw  Sugar  in  the  Philippine  and  Hawaiian  Islands. 
The    School    of    Mines    Quarterly,    Columbia    University,    July,    1913. — 

By-Products  of  Sugar  Manufacture,  and  Methods  for  Their  Utiliza- 
tion. 
Farmers  Bulletin,.  No.  52,  U.  S.  Department  of  Agriculture,  Washington. 

D.  C.— The  Sugar  Beet. 
Report  of  the  Eighth  International  Congress  of  Applied  Chemistry,  Vol. 

27-29. — The     Status    of     Cane     Sugar    and    Manufacture    in    the 

Hawaiian  Islands. 
Trade  Paper. — Sugar. 

CHAPTERS  XI  AND  XII.— ALCOHOLIC  BEVERAGES. 
Thorpe. — Dictionary  of  Applied  Chemistry. 
Sadtler,  Samuel. — Handbook  of  Industrial  Organic  Chemistry. 
Thorp,  Frank  H. — Outlines  of  Industrial  Chemistry. 
Harrington,  Charles. — Practical  Hygiene. 
Accum,   Frederick. — A  Treatise   of   Adulteration   of   Food   and   Culinary 

Poisons. 

Buchanan,  E.  D.  and  R.  E. — Household  Bacteriology. 
Conn,  H.  W. — Bacteria,  Yeasts  and  Molds  in  the  Home. 
Fowler,  G.  J. — Bacteriological  and  Enzyme  Chemistry. 
Osborn's    Annual    Guide,    December,    1903. — Vintage    and    Production    of 

Wines  and  Liquor. 
Bulletin  No.  13,  Part  Third,  U.  S.  Department  of  Agriculture,  Division 

of  Chemistry. — Fermented  Alcoholic  Beverages. 

Bulletin  No.  239,  Agricultural  Experiment  Station,  Ottawa,  Canada. 
Trade  Paper. — The  American  Brewer. 

CHAPTER  XIII.— FATS. 

Sadtler,  Samuel  P. — Handbook  of  Industrial  Organic  Chemistry. 
Thorp,  Frank  H. — Outlines  of  Industrial  Chemistry. 
Thorpe. — Dictionary  of  Applied  Chemistry. 
Wing,  Henry  W.— Milk  and  Its  Products. 


FOOD   INDUSTRIES  2QI 

Ward,  Artemus. — The  Grocers  Encyclopedia. 

Leffmann  and  Beam. — Food  Analysis. 

Wiley,  Harvey  W. — Foods  and  Their  Adulterations. 

International  Library  of  Technology. — Cottonseed  Oil  and  Products. 

Bulletin  No.   13,   Part  First,  U.   S.  Department  of  Agriculture,   Division 

of  Chemistry. — Dairy  Products. 
Bulletin  No.  163,  Agricultural  Experiment  Station,  Fort  Collins,  Colo. — 

Farm  Butter  Making. 
Farmers  Bulletin,  No.  241,  U.  S.  Department  of  Agriculture,  Washington, 

D.  C. — Butter  Making  on  the  Farm. 
Farmers  Bulletin,  No.  131,  U.  S.  Department  of  Agriculture,  Washington, 

D.  C. — Household  Tests  for  the  Detection  of  Oleomargarine  and 

Renovated  Butter. 

CHAPTER  XIV.— ANIMAL  FOODS. 
Wiley,  Harvey  W. — Foods  and  Their  Adulterations. 
Harrington,  Charles. — Practical  Hygiene. 
Hutchison,  Robert. — Foods  and  Dietetics. 
Jordan,  Whitman  H. — Principles  of  Human  Nutrition. 
Wilder,  F.  W.— The  Modern  Packing  House. 
Ward,  Artemus. — The  Grocers  Encyclopedia. 
The  National  Geographic  Magazine,  March,  1913. — Oysters :    The  World's 

Most  Valuable  Water  Crop. 
Bulletin  No.  114,  U.  S.  Department  of  Agriculture,  Bureau  of  Chemistry. — 

Meat  Extracts  and  Similar  Preparations. 
Farmers  Bulletin,  No.  391,  U.  S.  Department  of  Agriculture,  Washington, 

D.  C. — Economical  Use  of  Meat  in  the  Home. 
Farmers  Bulletin,  No.  183,  U.  S.  Department  of  Agriculture,  Washington, 

D.  C.— Meat  on  the  Farm. 
Farmers  Bulletin,  No.  85,  U.  S.  Department  of  Agriculture,  Washington, 

D.  C.— Fish  as  Food. 
Farmers  Bulletin,  No.  128,  U.  S.  Department  of  Agriculture,  Washington, 

D.  C.— Eggs  and  Their  Uses  as  Food. 

CHAPTER  XV.— THE  PACKING  HOUSE. 
Wilder,  F.  W.— The  Modern  Packing  House. 

International  Library  of  Technology. — Packing  House  Industries. 
The  Chemical  Engineer,  December,   1906. — Chemical  Engineering  in  the 

Packing  House. 

Morris  &  Co.— The  Pictorial  History  of  a  Steer. 
Wiley,  Harvey  W. — Foods  and  Their  Adulteration. 


292  FOOD   INDUSTRIES 

CHAPTER  XVI.— MILK. 

Winslovv,  K. — The  Production  and  Handling  of  Clean  Milk. 

Rosenau,  M.  J. — The  Milk  Question. 

Wing,  Henry  H. — Milk  and  Its  Products. 

Harrington,  Charles. — Practical  Hygiene. 

Buchanan,  E.  D.  and  R.  E. — Household  Bacteriology. 

Conn,  H.  W. — Agricultural  Bacteriology. 

Conn,  H.  W. — Storrs  Agricultural  Experiment  Station,  Report  1895 — 
Bacteria  in  the  Dairy. 

Leffmann  and  Beam. — Food  Analysis. 

Bulletin  No.  161,  U.  S.  Department  of  Agriculture,  Bureau  of  Animal 
Industry. — A  Study  of  the  Bacteria  which  Survive  Pasteurization. 

Bulletin  No.  104,  U.  S.  Department  of  Agriculture,  Bureau  of  Animal 
Industry. — Medical  Milk  Commission  and  the  Production  of  Cer- 
tified Milk  in  the  United  States. 

Bulletin  No.  107,  U.  S.  Department  of  Agriculture,  Bureau 'of  Animal 
Industry.— The  Extra  Cost  of  Producing  Clean  Milk. 

Farmer's  Bulletin,  No.  363,  U.  S.  Department  of  Agriculture,  Washington. 
D.  C.— The  Use  of  Milk  as  Food. 

CHAPTER  XVII.— MILK  PRODUCTS. 

Van  Slyke  and  Publow. — The  Science  and  Practice  of  Cheese-making. 

Wing,  Henry  H. — Milk  and  Its  Products. 

Wiley,  Harvey  W. — Foods  and  Their  Adulteration. 

Leffmann  and  Beam. — Food  Analysis. 

Luchsinger. — History  of  a  Great  Industry.  Address  at  the  State  His- 
torical Society  of  Wisconsin. 

The  National  Geographic  Magazine,  December,  1910. — A  North  Holland 
Cheese  Market. 

Bulletin  No.  13,  Part  First,  U.  S.  Department  of  Agriculture,  Division 
of  Chemistry. — Dairy  Products. 

Bulletin  No.  203,  New  York  Agricultural  Experiment  Station,  Geneva, 
New  York. — A  Study  of  Enzymes  in  Cheese*  . 

Bulletin  No.  219,  New  York  Agricultural  Experiment  Station,  Geneva. 
New  York. — Some  of  the  Compounds  Present  in  American  Cheddar 
Cheese. 

Bulletin  No.  236,  New  York  Agricultural  Experiment  Station,  Geneva, 
New  York. — Conditions  Affecting  Chemical  Changes  in  Cheese- 
making. 

Bulletin  No.  237,  New  York  Agricultural  Experiment  Station,  Geneva, 
New  York.— The  Role  of  the  Lactic  Acid  Bacteria  in  the  Manu- 
facture and  in  the  Early  Stages  of  Ripening  of  Cheddar  Cheese. 

Farmer's  Bulletin,  No.  487,  U.  S.  Department  of  Agriculture,  Washington. 
D.  C. — Cheese  and  Its  Economical  Uses  in  the  Diet. 


FOOD    INDUSTRIES  293 

CHAPTERS  XVIII  AND  XIX.— PRESERVATION  OF  FOODS. 

Appert,  Nicholas. — The  Art  of  Preserving  All  Kinds  of  Animal  and  Veg- 
etable Substances. 

Duckwall,  E.  W. — Canning  and   Preserving. 

Thresh  and  Porter. — Preservatives  in  Food  and  Food  Examination. 

Rideal,  Samuel. — Disinfection  and  the  Preservation  of  Foods. 

Wiley,  Harvey  W. — Foods  and  Their  Adulteration. 

Green,  Mary  E. — Food  Products  of  the  World. 

Bulletin  No.  13,  Part  Eighth,  U.  S.  Department  of  Agriculture,  Division 
of  Chemistry. — Canned  Vegetables. 

Bulletin  No.  151,  U.  S.  Department  of  Agriculture,  Bureau  of  Chem- 
istry.— The  Canning  of  Foods. 

Farmers  Bulletin,  No.  375,  U.  S.  Department  of  Agriculture,  Washington, 
D.  C.— The  Care  of  Food  in  the  Home. 

Farmers  Bulletin,  No.  359,  U.  S.  Department  of  Agriculture,  Washington, 
D.  C. — Canning  Vegetables  in  the  Home. 

Farmers  Bulletin,  No.  521,  U.  S.  Department  of  Agriculture,  Washington, 
D.  C. — Canning  Tomatoes  at  Home  and  in  Club  Work. 

Farmers  Bulletin,  No.  203,  U.  S.  Department  of  Agriculture,  Washington, 
D.  C. — Canned  Fruit,  Preserves  and  Jellies. 

CHAPTER  XX.— TEA,  COFFEE  AND  COCO. 

Freeman  and  Chandler. — The  World's  Commercial  Products. 

Thorpe. — Dictionary  of  Applied  Chemistry. 

Ward,  Artemus. — The  Grocers  Encyclopedia. 

Harrington,  Charles. — Practical  Hygiene. 

Fowler,  E.  J. — Bacteriological  and  Enzyme  Chemistry. 

Whymper,  R. — Coco  and  Chocolate;  Their  Chemistry  and  Manufacture. 

Harris,  W.  B. — Paper  on  Coffee  as  Affected  by  the  Food  and  Drug  Act. 

Count  Rumford. — Essay  on  The  Excellent  Qualities  of  Coffee  and  the 
Art  of  Making  it  in  the  Highest  Perfection. 

Leffmann  and  Beam. — Food  Analysis. 

Pan-American  Union  Bulletin,  1912. — The  Cacao  of  the  World. 

The  National  Geographic  Magazine,  October,  1911. — A  Visit  to  a  Brazilian 
Coffee  Plantation. 

Bulletin  No.  13,  Part  Seventh,  U.  S.  Department  of  Agriculture,  Wash- 
ington, D.  C. — Tea,  Coffee  and  Coco  Preparations. 

Farmers  Bulletin,  No.  301,  U.  S.  Department  of  Agriculture,  Washington, 
D.  C.— Home  Grown  Tea. 

Trade  Paper.— The  Tea  and  Coffee  Trade  Journal,  New  York. 


294  FOOD   INDUSTRIES 

CHAPTER  XXL— SPICES  AND  CONDIMENTS. 
Ridley,  Henry  N. — Spices. 

Gibbs,  W.  M. — Spices  and  How  to  Know  Them. 
Freeman  and  Chandler. — The  World's  Commercial  Products. 
Leffmann  and  Beam. — Food  Analysis. 
Wiley,  Harvey  W. — Foods  and  Their  Adulteration. 
Ward,  Artemus. — The  Grocer's  Encyclopedia. 
Conn,  H.  W. — Bacteria,  Yeasts  and  Molds  in  the  Home. 
Hoffman  and  Evans. — Journal  of  Industrial  and  Engineering  Chemistry. 

The  Use  of  Spices  as  Preservatives. 
Bulletin  No.  13,  Part  Second,  U.  S.  Department  of  Agriculture,  Division 

of  Chemistry. — Spices  and  Condiments. 
Trade  Paper.— The  Spice  Mill.     Spice  Mill  Publishing  Co.,  New  York. 


INDEX 

PAGE 

Acetic  ferment   98,   155,  174 

Acid  phosphate  of   lime 113 

Adulteration    59,   65,    71, 

73,  75,  81,  99,  152,  163,  170,  185,  195,  234,  254,  262,  268,  275,  286 

Albumins 12,   13,   148,   188,   190,   199,  212 

Albuminoids    13,     14 

Alcoholic  beverages    I53-I75 

brewing    155-164 

champagne    169 

cider   173 

classification    .' 153 

distilled   liquor    171-173 

fermentation    I54-I55 

historical    153 

koumiss    , 175 

vinegar    174 

wine  industry  165-171 

Alcoholic  solubles    13,     14 

Ale 164 

Allspice 209,  280,  285 

Alum    26,  27,  32.  99,   109,  1 10 

Amino-acid   13,   15,  230 

Animal   foods    187-200 

beef  extracts   191 

beef  juices   192 

eggs    197 

fish 193 

internal  organs 193 

meat    187 

shellfish    195 

Annatto    182,  245 

Ash  (see  Mineral  matter). 

Bacteria  22-31,  87,  88, 

98,  99,  179-181,  196,  198,  213-224,  225-232,  233-239,  242,  247-251 

Baking  powders  108-1 12 

alum  phosphate  m 

ammonia  1 12 

phosphate  no 

relative  efficiency  in 

tartrate  .  no 

20 


296  INDEX 


PAGE 

Barley    75,     76 

composition    75 

cultivation    75 

mill  products    76 

origin    75 

uses     75 

Beef  extracts   191,  208 

Beef   juices    ». 192 

Beef  viscera  inspection   203 

Beer   (see  Brewing). 

Beet  sugar   factories    142 

Benzoate  of   soda 235.   244,  280 

Berkef eld   filter    29 

Bicarbonate  of  soda 1 13-1 16 

Le  Blanc  method    114 

Solvay  process    115 

Niagara  process   1 16 

Biscuit  industry 102-104 

Blood    206,  207 

Bolter     •.     56 

Bolting   reel    : 57 

Bonded    whiskey 173 

Bone-black    113,    129,    149,  206 

Bone   products    206 

Boracic  acid 163,  209,  217,  235,  254 

Borax   32,  209,  217,  235,  254 

Brandy 171 

Breadmaking    84-102 

adulteration 99 

aerated  bread    101 

leavened  bread   87-91 

losses  in   fermentation    ' 100,  101 

modern  bread  factory   95-9-8 

primitive  methods'    84-86 

souring  and  its  prevention 98,     99 

steps  in  breadmaking   93~95 

yeast   preparations    91 

Bread  wrapping  machine    100,  101 

Breakfast   foods    77-82 

adulteration    81 

classification 77-8 1 

comparison  of  old  and  new 82 

Brewing    155-164 


INDEX  297 

PAGE 
Brewing  (continued} 

adulteration    163 

composition  of  beer   163 

kinds  of  beer 164 

processes  in  manufacture 156-163 

raw   material    155 

substitution 163 

Bromine    27 

Butter    177-182 

by-products 228,  229 

composition    177 

processes  in  manufacture 178-182 

renovated    182 

substitutes    182,  204 

Butterine   (see  Oleomargarine). 

Buttermilk    228 

Butyric   ferment 98,  212 

By-products 112,  113,   122,   150,  170,  201,  203-209,  228,  229 

Caffein 262,  263,  269 

Calves   brains    193 

Can  closing  machines 253 

Cane   crushers 134 

Cane  mill    133 

Canning  industry    247-254 

adulteration    254 

containers    25 1 

historical    247 

meat  products    25 1 

processes  in  manufacture   ' 248 

success  of  canning 250 

Carbohydrates    .' 7-1 1 

classification    8 

formation     8 

important  properties   10 

occurrence    9 

Carbon  dioxide 35,  90,  101,  no,  in,  154 

Carbonic  acid  gas  generator 34 

Cardine    209 

Cassava 85,  118 

Cassia    282 

Caviar    : 197 

Cellulose   9 


298  INDEX 


PAGE 

Centrifuge    139 

Cereals     66-76 

adulteration    71 

barley    75,     76 

biological  origin    66 

composition    67 

corn    67 

geographical    distribution    66 

kinds    66 

oats 74,    75 

r  i  ce     ' 7 1-74 

use  in  our  country 66 

Cereal  Department    63 

Champagne    169 

Cheese    229-234 

adulteration    234 

composition    230 

historical    229 

processes  in  manufacture   230-233 

uncured    233 

Chlorine    27 

Chocolate    274 

Cholera    22,     27 

Cholera   infantum    217 

Churning    181 

Cider    173 

Cinnamic  aldehyde    280 

Cinnamon    209.   280,  282 

Citrate  of  lime   213 

Clotting    15 

Cloves    209,  280,  283 

Coagulated  proteins    ". 13,     15 

Coagulation    15 

Coal  tar  dyes 105,  182,  245,  254 

Cochineal    245,  254 

Cockle  cylinder   53 

Coco 270-276 

adulteration    275 

as  a  beverage 275 

cultivation 270 

historical    270 

preparation  of  chocolate    : 274 

preparation  of  coco    275 


299 

Coco  (continued)  PAGE 

processes  of  manufacture  272 

Coffee  263-270 

adulteration  268 

as  a  beverage  269 

cultivation  265 

extracts  270 

historical  263 

processes  of  manufacture  265-268 

the  coffee  plant  264 

Coffee   substitutes 82,    83 

Cold  storage   199,  237,  238 

Collagen    187 

Coloring  matter 182,  209,  232,  245,  246,  254,  275 

Condiments  (see  Spices). 

Copper   boilers 160 

Copper   sulphate    245,  254 

Corn  (see  Indian  corn). 

Cornmeal    69 

Corn  oil    125 

Corn  syrup   (see  Glucose). 

Cottonseed  oil   185,  186 

Crackers  (see  Biscuit  industry). 

Cream  of  tartar    112,  113 

Cream  separators   179,  180 

Creatin     192 

Creatinin    192 

Creosote    241,  242 

Crushers    123 

Curdling    15 

Dextrins 127,  128 

production   of    127 

occurrence    10 

uses   for    127 

Diastase    157,  158 

Diffusion   battery    144-146 

Distillation    29,  172 

Domestic  niters 28,     29 

Dough  divider   98,     99 

Dough  mixing  machine   97 

Dripping   boxes    126,  127 

Eggs    197-200 


300  INDEX 

Eggs   (continued)  PAGE 

composition  of  the  egg 199 

composition  of  the  shell 198 

methods   of   preservation    198 

physical   structure    197 

Elastin    187 

Emulsification    12 

Ensilage    " 150 

Extractives    15,  192 

Facing    262,  269 

Fats    11-13,    176-186 

butter    177-182 

butter   substitutes    182-184 

composition    1 1 

cottonseed  oil    185 

extraction    176 

occurrence    1 1 

olive  oil   185 

peanut  oil  186 

properties    12 

purification    176 

utilization   of    204,  205 

Fertilizer   150,   186,  207 

Fermentation  88-90,  154,  161,  167,  260,  266,  272 

Filter  bags    148 

Filter  bed    24,   25,    26 

Filter  plant    27 

Filter  press 124,  125,  135,  146,  159,  162,  185,  186 

Fish IQ3-IQ5 

adulteration    195 

edible  portion    195 

nutritive  value   195 

shellfish 195 

Flour    44-6i 

adulteration    59 

bleaching  of 59 

composition    67 

entire  wheat 61 

gluten 63 

Graham 60 

hard  wheat   60 

milling  of    44~59 

prepared    60 


INDEX  3OI 

Flour   (continued)  PAGE 

soft  wheat    60 

sifter  and  blender 96 

testing  of    58 

Food   principles    5-15 

Force 79 

Formaldehyde 217,   219,   235,  241 

Fructose    9 

Galactose 9 

Gelatin    187,  207 

Ginger    280,  285 

Globulin   13,   14,  212 

Glucose 128,  129 

occurrence    9 

processes  of  manufacture    128,  129 

uses     128 

Glue    : 207 

Glutelins    13,  14 

Gluten  feed   125 

Glycogen   • 8,   10,   188,  195 

Grape-Nuts    80 

Grape  sugar  (see  Glucose). 

Hominy    69 

Hops     156,  160 

Hulled  corn    68 

Hydraulic  presses    , 124 

Hydrolysis    10 

Ice    supply 31 

Indian   corn    67-71 

composition 67 

early   cultivation    68 

early  methods  of  preparation 68 

modern  milling    69 

old  milling  methods 69 

origin 67 

uses 70 

varieties    68 

Invert  sugar I ! 

Jaggery    : I5I 

Kidney    14,  IQ3 


3O2  INDEX 

PAGE 
Koumiss    175 

Lactic  ferment 98,  155,   180,  212,  231 

Lacto-chrome    213 

Lactose  or  milk  sugar 9,  212,  228 

Lard    205,  234,  275 

Lardine  (see  Oleomargarine). 

Leavening  agents    107-1 16 

acid  phosphate  of  lime 113 

alum   phosphate  powders    in 

ammonia  powders    112 

baking  powders    108 

bicarbonate  of  soda  113 

chemical  agents    107 

cream  of  tartar    1 12 

early  use  of  chemical  agents 108 

phosphate  powders    no 

relative  efficiency   in 

tartaric   acid    113 

tartrate   powders    ; 1 10 

yeast    '. 107 

Lecithin    200 

Liberwurst    193 

Lithia    32 

Liver    14,  193 

Logwood 245 

Macaroni     104-106 

Mace    285 

Maize  (seef  Indian  corn). 

Malic    acid    165,  170 

Malting    156-159 

Maltose 9 

Massecuite    138 

Meat    187-191 

canning    208 

changes  in  cooking  190 

chemical  constitution    187 

extracts    191 

inspection 189 

internal  organs    193 

physical   structure    187 

reasons  for  cooking   190 


INDEX  303 

PAGE 

Medulline    209 

Menhaden 68 

Meta-protein    13,   15,  230 

Middlings    50,   54-56,  63 

Milk     210-223 

certified     222 

composition    .- 211 

diseases   from    216 

importance  of  the  supply 213 

modified    223 

necessity  for  cleanliness    217 

our  duty  to  the  producer 219 

pasteurization    222 

source 210 

sterilization    219 

testing    219 

Milk  bottling  machine    221 

Milk  coolers    221 

Milk  products    224-234 

artificially  soured  milk    ^ 229 

buttermilk    228 

cheese 229-234 

concentrated   milk    227 

condensed   milk    224 

dried   casein    228 

evaporated   milk    226 

milk  powders    227 

milk  sugar   228 

Milling    44-59 

advantages  of  new  processes 57 

cleaning  of  wheat .' 52 

diagram  of  modern  processes 50 

disadvantages  of  old  processes , 49 

grist  mills 47 

hand-stones    44 

mortar  and  pestle   45 

quern    46 

reduction  of  the  middlings 55 

roller  mills    49,  53 

separation  of   the  middlings t 53 

tempering    53 

wheat    blends    59 

Mill-pick    47 


3O4  INDEX 


PAGE 

Mineral  matter   5,  6,  22, 

32,  70,  72,  74,  143,  150,  165,  188,  195,  198,  213,  230,  263 

Mineral  waters    32-35 

artificial 35 

medicinal  power    33 

natural   springs    32,     33 

water,   classification    32 

Mineral  springs    33 

Molasses    136,    146,  151 

Molds 87,  88,  233,  235.  236.  239,  242 

Multiple-effect  evaporating  apparatus    137 

Musculine    209 

Mustard    . .  .• 280,  282 

Myosin    1 88,  190 

Neats-f oot  oil    206 

Nucleo-protein    14 

Nutmeg 280,  285 

Oats 74,     75 

adulteration    75 

composition    67,     74 

milling   75 

mill   products    74 

Oatmeal    74 

Oleomargarine    182-184,  204 

Olive   oil    184,  185 

Open  pan  evaporators 135 

Oysters    IQ5-IQ7 

Packing  house    201-209 

beef    extracts    208 

blood    206 

bone  products   206 

butterine    204 

canning  of  meats 208 

fertilizers 207 

gelatin    207 

glue    207 

growth  and  breadth  of  the  industry 201 

hides,  pelts  and  bristles 203 

historical    .  .  201 


INDEX  305 

PAGE 
Packing  house   (continued) 

inspection   and    slaughtering    202 

lard    205 

minor  products    209 

neats-f oot  oil  , 206 

tallow 204 

tankage    206 

sausages    208,  241 

Pancreas    14,    IQ3,  209 

Pancreatin    209 

Paragol    125 

Pasteurization    162,   220-222 

Peanut  oil    186 

Pepper 209,   280,  281 

Pepsin    209 

Peptase    . 159 

Peptone   13,   15,   163,  230 

Phosphoprotein    14,  199 

Plumping    196 

Plastering    168 

Porter 164 

Preservation  of  foods    235-254 

alcohol    243 

canning   247-254 

cooling    237 

drying    235 

salting 239 

smoking    240 

sterilization    219,   247,  250 

sugaring 239 

use  of  fats  and  oils 242 

use   of   preservatives    243 

use  of  spices   243 

Preservatives    243-246 

Proteins     13-15 

classification    13 

composition    13 

occurrence 14 

properties    15 

Proteoses 13,     15 

Prussian   blue    245,  262 

Puffed   Rice    78 

Purifier    56 


306  INDEX 

PAGE 

Rennet    232 

Renovated  butter   182 

Rice    71-74 

adulteration    73 

composition    67,     72 

cultivation 72 

geographical    distribution    72 

milling    72 

origin    71 

uses    73 

Roller   mills    53,  158 

Rum    171 

Rye    .- 64-65 

adulteration 65 

composition    64,     67 

uses    64 

Saccharine    245,  254 

Saffron 105,    182,  245 

Salicylic  acid   163,   174,  217,  235 

Salt   86,   181,   184,  233,  277 

Salting    .239 

Samp    69 

Saponification    13 

Sarco-lactic   acid    188 

Sausages    208,   241,  279 

Sauteing    191 

Scalper    53 

Scourer    53 

Scrapple    208 

Sedimentation  basin    23 

Seminola 64 

Separators    52,  124 

Shellfish    x -. I9S-I97 

Shorts 63 

Shredded  Wheat   Biscuit 80 

Smoking    240 

Sodium  hypochlorite   27 

Sodium  silicate • 199 

Spices  and  condiments 277-287 

adulteration    286 

allspice 285 

as  preservatives    279 


INDEX  307 

PAGE 
Spices  and  condiments   (continued) 

cinnamon  and  cassia    282 

cloves    283 

ginger    285 

mustard    282 

nutmeg  and  mace   '. . .  285 

pepper   209,  280,  281 

salt    277 

uses    279 

vanilla    280 

vinegar    174,  287 

Sterilization    219,  226,  247,  250 

Starch    1 17-129 

composition  and  formation    8 

corn  starch  industry 122-129 

occurrence    9 

outline  of  corn  products  industry 121 

physical   characteristics    117 

physical  and  chemical  properties 117 

potato  starch    1 18,  1 19 

source  of  supply    1 18 

tapioca    , 120,  121 

Stock  boilers   249 

Strike  pan    138 

Stout    164 

Sucrose  (see  Sugar). 

Sugar 130-152 

adulteration    152 

beet  sugar  industry   140-147 

block   sugar    149 

cane  sugar  industry    132-140 

cane  syrup    : 152 

comparison  of  cane  and  beet  sugar 131 

date  palm   sugar    151 

history  of  the  sugar  beet 130 

history  of  the  sugar  cane 130 

maple  sugar    151 

powdered  sugar    132 

properties    132 

refining    147-149 

sorghum    151 

source    130 

utilization  of  the  by-products 150 


308  INDEX 


PAGE 
Sugar  (continued) 

yellow    sugar    150 

Sweetbreads    193 

Tallow    204 

Tannic  acid   170,  261,  262,  263,  269 

Tartaric  acid  113,   165,  170 

Tea    255-263 

adulteration    262 

as  a  beverage   262 

classification    < 257 

composition    263 

culture  of  the  plant 255 

green  tea    261 

historical    255 

processes  in  manufacture   259-262 

rules    for    tea    making 262 

Tea   plant    256 

Theobromine    275 

Thymus  gland 193.  209 

Thyroidine    209 

Tongue    193 

Tortillas 85 

Trachina    189 

Tripe    193 

Tuberculosis    189,  216 

Turmeric    245 

Typhoid   fever    23,    196,  226 

Vacuum  pan    136-139,  226 

Vanilla 280 

Vanillin    280 

Vinegar    174,    i?5,  287 

Vodka    i?2 

Water    16-35 

atmospheric    18 

classification  of  natural  water 16 

classification  of  potable  water 18 

contamination  of   public  supply. 21 

contamination  of  wells 20 

danger  of  impure 22 

diseases   from      22 


INDEX  309 

PAGE 

Water  (continued) 

history  of  the  water  supply 17 

ice   supply    31 

importance   of    7 

judging  a  supply   31 

mineral    32-35 

pollution  of  wells   20 

purification    23-30 

subsoil    . 19 

surface    19 

Water  glass   (see  Sodium  silicate). 

Wheat    36-64 

composition    36,     67 

cultivation 3'9 

geographical    distribution 37 

milling    (old  processes) • 44~5i 

milling    (new   processes) v  .  .52-59 

origin 36 

structure  of  the  grain 41 

value   of    42 

varieties     43 

Whiskey    % 172,  173 

Wild  beet    140 

Wine 165-171 

adulteration    170 

champagne    169 

composition    170 

improving   wines    168 

preservation    171 

processes  in  manufacture   166-168 

sophisticated    170 

Wort    160 

Yeast   87-91,   154,  155 

Yeast  preparations 91-93 

brewers    91 

compressed    92 

dried 93 


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